Information recording medium, method for recording information, and method for reproduction information

ABSTRACT

An information recording medium includes a first area (DA 2 ) for storing picture data for forming a plurality of pictures, a second area (DA 21 ) which is included in the first area and stores control data of the picture data, and a third area (INFO 1 ) which is included in the second area and stores specifying data for specifying the storage position of representative picture data for forming a representative picture in the plurality of pictures.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to an information recording mediumsuch as a DVD (Digital Video Disk)-RAM (Random Access Memory) forrecording predetermined information.

[0002] The present invention also relates to an information recordingmethod for recording information on an information recording medium suchas a DVD-RAM for recording predetermined information.

[0003] The present invention further relates to an information playbackmethod for playing back information recorded on an information recordingmedium such as a DVD-RAM for recording predetermined information.

[0004] In recent years, systems for playing back the contents of opticaldiscs that record video data (moving pictures), audio data, and the likehave been developed, and have prevailed for the purpose of playing backmovie software titles, karaoke data, and the like as in LDs (laserdiscs), video CDs (video compact discs), and the like. Information aboutrecording contents such as titles is generally printed on the surfacesof such optical discs. Further, information about recording contentssuch as titles is generally added to the packages of these opticaldiscs. This allows the user to obtain the recording contents of anoptical disc without playing back the optical disc.

[0005] DVD standards that use MPEG2 (moving picture expert group)international standards, and also use an audio compression scheme suchas AC-3 (digital audio compression), or the like, have been proposed.The DVD standards include read-only DVD video (or DVD-ROM), write-onceDVD-R, and recordable/readable DVD-RW (or DVD-RAM).

[0006] The DVD video (DVD-ROM) standards support MPEG2 as a movingpicture compression scheme, and AC-3 audio and MPEG audio in addition tolinear PCM as audio recording schemes in accordance with the MPEG2system layer. Furthermore, the DVD video standards are configured byadding sub-picture data obtained by runlength-compressing bitmap datafor superimposed dialogs, and presentation control data (navigationdata) for fastforward, rewind, data search, and the like. The standardsalso support the UDF Bridge format (a hybrid of UDF and ISO9660) toallow computers to read data.

[0007] An optical disc currently used in DVD video (DVD-ROM) is asingle-sided, single-layered 12 cm disc having a storage amount around4.7 GB (gigabytes). A single-sided, two-layered disc has a storageamount around 9.5 GB, and a double-sided, two-layered disc is capable ofrecording a large amount of data around 18 GB (when a laser of awavelength of 650 nm is used for reading).

[0008] An optical disc currently used in DVD-RW (DVD-RAM) is a 12 cmdisc, and has a storage amount of 2.6 GB (gigabytes) on one surface,i.e., 5.2 GB on the two surfaces. The currently available DVD-RAMoptical disc has a smaller storage amount than that of a DVD-ROM disc ofthe corresponding size. However, technical developments for expandingthe amount of the DVD-RAM disc have been extensively made, and it iscertain that a DVD-RAM disc having a storage amount more than 4.7 GB onone surface will be available in the near future.

[0009] However, since an MPEG2 video file that can obtain high picturequality has a large data size, the currently available DVD-RAM disc(single-sided 2.6 GB disc or double-sided 5.2 GB disc) does not alwayshave a sufficient recordable time (around 1 hour for 2.6 GB disc, around2 hours for 5.2 GB disc).

[0010] Since the user can freely record data on the DVD-RAM disc, noinformation representing recording contents is generally printed on thedisc surface. For the same reason, no information representing recordingcontents is generally printed on the package of the DVD-RAM disc.

[0011] To obtain the recording contents of the DVD-RAM disc at a glanceat the disc appearance, the user must perform the following process. Forexample, the user grasps recording contents recorded on the DVD-RAMdisc. The user creates information representing the recording contentsof the DVD-RAM disc. The user writes the information representing therecording contents of the DVD-RAM disc on the disc surface.Alternatively, the user may add information representing the recordingcontents of the DVD-RAM disc to the disc package.

[0012] Since no information about recording contents is printed on theDVD-RAM disc, as described above, the user cannot obtain the recordingcontents of the optical disc at a glance at the disc appearance.

[0013] To obtain the recording contents of the optical disc at a glanceat the appearance of the DVD-RAM disc, the user must performpredetermined processing for the disc.

BRIEF SUMMARY OF THE INVENTION

[0014] The present invention has been made to solve the above problems,and has as its object to provide the following information recordingmedium, information recording method, and information playback method.

[0015] (1) There is provided an information recording medium which cancontribute to easy display of information about the recording contentsof the information recording medium without any playback and cumbersomeprocessing of the information recording medium (DVD-RAM disc).

[0016] (2) There are provided an information recording method andinformation playback method which can easily display information aboutthe recording contents of an information recording medium without anyplayback and cumbersome processing of the information recording medium.

[0017] To achieve the above objects, the information recording medium,information recording method, and information playback method accordingto the present invention have the following arrangements.

[0018] (1) The information recording medium according to the presentinvention comprises a first area for storing picture data for forming aplurality of pictures, a second area which is included in the first areaand stores control data of the picture data, and a third area which isincluded in the second area and stores specifying data for specifying astorage position of representative picture data for forming arepresentative picture in the picture data.

[0019] (2) The information recording method according to the presentinvention comprises the first step of playing back an informationrecording medium having a first area for storing picture data forforming a plurality of pictures, a second area which is included in thefirst area and stores control data of the picture data, and a third areawhich is included in the second area and stores specifying data forspecifying a storage position of representative picture data for forminga representative picture in the picture data, and the second step ofobtaining the representative picture data on the basis of the specifyingdata obtained by playback in the first step, and printing out therepresentative picture based on the obtained representative picturedata.

[0020] (3) The information playback method according to the presentinvention comprises the first step of playing back an informationrecording medium having a first area for storing picture data forforming a plurality of pictures, a second area which is included in thefirst area and stores control data of the picture data, and a third areawhich is included in the second area and stores specifying data forspecifying a storage position of representative picture data for forminga representative picture in the plurality of pictures, and the secondstep of obtaining the representative picture data on the basis of thespecifying data obtained by playback in the first step, and displayingthe picture based on the obtained representative picture data.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0021]FIG. 1 is a perspective view for explaining the structure of arecordable/readable optical disc (DVD-RAM or DVD-RW disc);

[0022]FIG. 2A is a view showing the state in which the optical discshown in FIG. 1 is stored in a cartridge;

[0023]FIG. 2B is a view showing the schematic arrangement of recordingtracks on the data recording area of the optical disc shown in FIG. 1;

[0024]FIG. 3 is a view for explaining the hierarchical structure ofinformation (the contents of the data recording area or a volume spaceof DVD video) recorded on the optical disc in FIG. 1;

[0025]FIG. 4 is a view showing information included in a lead-in area;

[0026]FIG. 5 is a view showing information included in volume/filemanagement information;

[0027]FIG. 6 is a view for explaining information included in playbackcontrol information;

[0028]FIG. 7 is a view for explaining information included in menu indexinformation;

[0029]FIG. 8 is a view for explaining information included in controlinformation and a video object;

[0030]FIG. 9 is a view for explaining the logical structure ofinformation (lead-in area) recorded on the optical disc in FIG. 1;

[0031]FIG. 10 is a view for explaining the directory structure ofinformation (data file) recorded on the optical disc in FIG. 1;

[0032]FIG. 11 is a view for explaining the hierarchical structure ofinformation included in video object set VTSTT_VOBS in FIG. 8;

[0033]FIG. 12 is a view for explaining the contents of packs in thelowermost layer of the hierarchical structure in FIG. 11;

[0034]FIG. 13 is a view for explaining the contents of a PCI packet inFIG. 12;

[0035]FIG. 14 is a view for explaining the contents of video managerinformation VMGI in FIG. 8;

[0036]FIG. 15 is a view for explaining the contents of video managerinformation management table VMGI₁₃ MAT in FIG. 14;

[0037]FIG. 16 is a view for explaining the contents of video title setinformation VTSI in FIG. 8;

[0038]FIG. 17 is a view for explaining the contents of video title setinformation management table VTSI_MAT in FIG. 16;

[0039]FIG. 18 is a view for explaining the contents of program chaingeneral information PGC_GI;

[0040]FIG. 19 is a block diagram for explaining the arrangement of anapparatus (DVD video recorder) for recording/playing back digital movingpicture information at a variable recording rate using the informationwith the structures described with reference to FIGS. 3 to 18 on thedisc in FIG. 1;

[0041]FIG. 20 is a view showing an example of a remote controller foroperating the DVD video recorder in FIG. 19;

[0042]FIG. 21 is a flow chart for explaining printing of informationabout the recording contents of the optical disc;

[0043]FIG. 22 is a view showing the state in which picture informationis printed on a label added to the optical disc and cartridge;

[0044]FIGS. 23A, 23B, and 23C are views showing the state in whichamount information is printed on a label added to the cartridge;

[0045]FIGS. 24A and 24B are views showing the state in which rewritecount information is printed on a label added to the optical disc;

[0046]FIG. 25 is a view schematically showing a data structure recordedon the optical disc in a modification;

[0047]FIG. 26 is a view for explaining the directory structure of theoptical disc having the data structure shown in FIG. 25;

[0048]FIG. 27 is a view schematically showing a data structure in an AVfile;

[0049]FIG. 28 is a view showing the recording location of a video objecton the optical disc;

[0050]FIG. 29 is a view schematically showing a data structure in anallocation map table;

[0051]FIG. 30 is a view schematically showing example 1 of the datastructure of RTRW video manager information;

[0052]FIG. 31 is a view schematically showing example 2 of the datastructure of RTRW video manager information;

[0053]FIG. 32 is a view schematically showing example 3 of the datastructure of RTRW video manager information;

[0054]FIG. 33 is a view showing the schematic structure of data in PGCcontrol information; and

[0055]FIG. 34 is a view showing an example of playback of video datausing PGC.

DETAILED DESCRIPTION OF THE INVENTION

[0056] A digital information recording/playback system according to anembodiment of the present invention will be explained hereinafter withreference to the accompanying drawings.

[0057] As a typical embodiment of a digital informationrecording/playback system according to the present invention, anapparatus which records/plays back moving pictures encoded by MPEG2 at avariable bit rate, e.g., a DVD digital video recording, is known. (Anexample of the DVD digital video recorder will be described in detaillayer).

[0058]FIG. 1 is a perspective view for explaining the structure of arecordable/readable optical disc 10 used in the DVD digital videorecorder.

[0059] As shown in FIG. 1, this optical disc 10 has a structure obtainedby adhering a pair of transparent substrates 14 each having recordinglayer 17 using adhesive layer 20. Each substrate 14 can be formed of a0.6 mm thick polycarbonate film, and adhesive layer 20 can consist of avery thin (e.g., 40 μm thick) ultraviolet setting resin. When the pairof 0.6 mm thick substrates 14 are adhered to each other so that theirrecording layers 17 contact each other on the surfaces of adhesive layer20, a 1.2 mm thick large-amount optical disc 10 is obtained.

[0060] Optical disc 10 has center hole 22, and clamp areas 24 used forclamping optical disc 10 upon its rotation are formed around center hole22 on the two surfaces of the disc. Center hole 22 receives the spindleof a disc motor when optical disc 10 is loaded into a disc drive (notshown). Optical disc 10 is clamped at its clamp areas 24 by a discdamper (not shown).

[0061] Optical disc 10 has information areas 25 that can record videodata, audio data, and other information around clamp areas 24 on its twosurfaces.

[0062] Each information area 25 has lead-out area 26 on its outerperiphery side, and lead-in area 27 on its inner periphery side thatcontacts clamp area 24. The area between lead-out and lead-in areas 26and 27 is defined as data recording area 28.

[0063] On recording layer (optical reflection layer) 17 of informationarea 25, a recording track is continuously formed in, e.g., a spiralpattern. The continuous track is divided into a plurality of physicalsectors, which have serial numbers. Various data are recorded on opticaldisc 10 using these sectors as recording units.

[0064] Data recording area 28 serves as an actual data recording area,and records video data (main picture data) such as a movie or the like,sub-picture data such as superimposed dialogs, menus, and the like, andaudio data such as words, effect sounds, and the like as similar pittrains (physical shapes or phase states that bring about change inoptical conditions).

[0065] When optical disc 10 is a double-sided recording RAM disc inwhich each surface has one recording layer, each recording layer 17 canbe formed by three layers, i.e., by sandwiching a phase-change recordingmaterial layer (e.g., Ge₂Sb₂Te₅) between two zinc sulfide.silicon oxide(ZnS.SiO₂) mixture layers.

[0066] When optical disc 10 is a single-sided recording RAM disc inwhich each surface has one recording layer, recording layer 17 on theside of read-out surface 19 can be formed by three layers including thephase-change recording material layer. In this case, layer 17 on theside opposite to read-out surface 19 need not be an informationrecording layer but may merely be a dummy layer.

[0067] When optical disc 10 is a one-side read type two-layered RAM/ROMdisc, two recording layers 17 can comprise a single phase-changerecording layer (on the side farther from read-out surface 19;read/write), and a single semi-transparent metal reflection layer (onthe side closer to read-out surface 19; read-only).

[0068] When optical disc 10 is a write-once DVD-R, a polycarbonatesubstrate is used, gold can be used as a reflection layer (not shown),and an ultraviolet setting resin can be used as a protection layer (notshown). In this case, an organic dye is used in recording layer 17. Asthe organic dyes, cyanine, squarilium, chroconic, and triphenylmenthanedyes, xanthene and quinone dyes (naphthoquinone, anthraquinone, and thelike), metal complex dyes (phthalocyanine, porphyrin, dithiol complex,and the like), and so forth can be used.

[0069] Data can be written on such DVD-R disc using a semiconductorlaser having a wavelength of 650 nm and an output of about 6 to 12 mW.

[0070] When optical disc 10 is a one-side read type two-layered ROMdisc, two recording layers 17 can be comprised of a single metalreflection layer (on the side farther from read-out surface 19) and asingle semi-transparent reflection layer (on the side closer to read-outsurface 19).

[0071] In case of read-only DVD-ROM disc 10, pit trains are pre-formedby a stamper on substrate 14, and a reflection layer of, e.g., a metal,is formed on that surface of substrate 14, which is formed with pittrains. The reflection layer is used as recording layer 17. In suchDVD-ROM disc 10, no grooves serving as recording tracks are especiallyformed, and the pit trains formed on the surface of substrate 14 serveas tracks.

[0072] In various types of optical discs 10 described above, read-onlyROM information is recorded on as recording layer 17 as an embossedpattern signal. By contrast, no such embossed pattern signal is formedon substrate 14 having read/write (or write-once) recording layer 17,and a continuous groove is formed instead. A phase-change recordinglayer is formed on such groove. In case of a read/write DVD-RAM disc,the phase-change recording layer in land portions is also used forinformation recording in addition to the groove.

[0073] When optical disc 10 is of one-side read type (independently ofone or two recording layers), substrate 14 on the rear side viewed fromread-out surface 19 need not always be transparent to the read/writelaser beam used. In this case, a label may be printed on the entiresurface of substrate 14 on the rear side.

[0074] A DVD digital video recorder (to be described later) can bedesigned to attain repetitive recording/ repetitive playback(read/write) for a DVD-RAM disc (or DVD-RW disc), singlerecording/repetitive playback for a DVD-R disc, and repetitive playbackfor a DVD-ROM disc.

[0075]FIG. 2A is a view showing the state in which the optical discshown in FIG. 1 is stored in a cartridge. FIG. 2B is a view showing theschematic arrangement of recording tracks on the data recording area ofthe optical disc shown in FIG. 1.

[0076] When disc 10 is a DVD-RAM (or DVD-RW), disc 10 itself is storedin cartridge 11 to protect its delicate disc surface. When DVD-RAM disc10 in cartridge 11 is inserted into the disc drive of a DVD videorecorder (to be described later), the shutter of cartridge 11 opens,disc 10 is clamped by the turntable of a spindle motor (not shown) androtated to face an optical head (not shown).

[0077] On the other hand, when disc 10 is a DVD-R or DVD-ROM, disc 10itself is not stored in cartridge 11, and bare disc 10 is directly seton the disc tray of a disc drive.

[0078] Recording layer 17 of information area 25 shown in FIG. 1 isformed with a continuous data recording track in a spiral pattern. Thecontinuous track is divided into a plurality of logical sectors (minimumrecording units) each having a given storage amount, as shown in FIG.2B, and data are recorded with reference to these logical sectors. Therecording amount per logical sector is determined to be 2,048 bytes (or2 kbytes) which are equal to one pack data length (to be describedlater).

[0079] Data recording area 28 is an actual data recording area, whichsimilarly records management data, main picture (video) data,sub-picture data, and audio data.

[0080] Note that data recording area 28 of disc 10 shown in FIG. 2A canbe divided into a plurality of ring-shaped (annular) recording areas (aplurality of recording zones), although not shown. The disc rotationalvelocity varies in units of recording zones. However, within each zone,a constant linear or angular velocity can be set. In this case, anauxiliary recording area (free space or area) can be provided for eachzone. These free spaces in units of zones may collectively form areserve area for that disc 10.

[0081]FIG. 3 to FIG. 11 are views for explaining the hierarchicalstructure of information recorded on optical disc 10 shown in FIG. 1.

[0082] Data recording area 28 formed on optical disc 10 shown in FIG. 1has a structure, as shown in FIG. 3. The logical format of thisstructure is defined to comply with, e.g., the Universal Disk Format(UDF) Bridge (a hybrid of UDF and ISO9660) as one of standard formats.

[0083] Data recording area 28 between lead-in area 27 and lead-out area26 is assigned as a volume space. Volume space 28 can include a spacefor information of the volume and file structures (volume/filemanagement information 70), and a space for the application of the DVDformat (data area (rewritable) DA).

[0084] Volume space 28 is physically divided into a large number ofsectors, and these physical sectors have serial numbers. The logicaladdresses of data recorded on this volume space (data recording area) 28mean logical sector numbers, as defined by ISO9660 and the UDF Bridge.The logical sector size in this space is 2,048 bytes (or 2 kbytes) asthe effective data size of the physical sector. The logical sectornumbers are assigned serial numbers in ascending order of physicalsector numbers.

[0085] Unlike the logical sectors, each physical sector is added withredundant information such as error correction information and the like.For this reason, the physical sector size does not strictly match thelogical sector size.

[0086] That is, volume space 28 has a hierarchical structure, whichincludes volume/file management information 70 and data area DA. Theseareas included in volume space 28 are split up on the boundaries oflogical sectors. Note that one logical sector is defined to be 2,048bytes, and one logical block is also defined to be 2,048 bytes. Hence,one logical sector is defined equivalently with one logical block.

[0087] Volume/file management information 70 corresponds to a managementarea defined by ISO9660 and the UDF Bridge.

[0088] The embossed data area of lead-in area 27 records in advanceinformation about the outline of the information recording medium,information about recording, playback, and erase characteristics, andinformation about the manufacture of the information recording medium.Information about the outline of the information recording medium isinformation such as the disc type (DVD-RAM, DVD-ROM, CD-ROM, or thelike) of optical disc 10, the disc size, the recording density, thephysical sector number representing the recording start/recording endposition, and the like. Information about recording, playback, and erasespecifications is information such as the recording power, the recordingpulse width, the erase power, the playback power, the recording/eraselinear velocity, and the like. Information about the manufacture of theinformation recording medium is information such as the manufacturingnumber.

[0089] The rewritable areas of lead-in and lead-out areas 27 and 26 haveunique disc name recording areas for identifying the informationrecording medium, test recording areas (for confirming recording/eraseconditions), and defective management information recording areas aboutdefective areas in data area DA. These areas allow recording by thedigital information recording/playback system.

[0090] Data area DA includes a data recording area for recordingpredetermined data. Data area DA allows mixed recording of computerdata, audio data, and video data. In this data area DA, the recordingorder and recording information sizes of computer data, audio data, andvideo data can be arbitrarily set. In FIG. 3, areas which recordcomputer data will be called computer data areas DA1 and DA3, and anarea which records audio & video data will be called audio & video dataarea DA2.

[0091] Audio & video data area DA2 records control information DA21,video object DA22, picture object DA23, and audio object DA24. Controlinformation DA21 is control information necessary for processes such aspicture recording (sound recording), playback, editing, and search.Video object DA22 is recording information (moving picture data) ascontents of video data. Picture object DA23 includes still pictures suchas slides and stills, information for searching video data for targetdata, and information about an edit thumbnail in video data. Audioobject DA24 is sound recording information as contents of audio data.

[0092] Control information DA21 includes playback control informationDA211, recording control information DA212, edit control informationDA213, and reduced drawing control information DA214. Playback controlinformation DA211 is control information necessary for playback.Recording control information DA212 is control information necessary forrecording (picture recording and sound recording). Edit controlinformation DA213 is control information necessary for editing. Reduceddrawing control information DA214 includes information for searchingvideo data for target data, and management information about an editthumbnail in video data.

[0093] Reduced drawing control information DA214 includes anchor pointerDA2141 and picture address table DA2142. Picture address table DA2142records menu index information INFOL, index picture information INFO2,slide & still picture information INFO3, information picture informationINFO4, defective area information INFO5, and wallpaper pictureinformation INFO6.

[0094] Information included in lead-in area 27 will be described withreference to FIG. 4.

[0095] The lead-in area 27 includes a data recording area for recordingamount information 271. Amount information 271 has a data recording areafor recording total amount information 2711 and free area information2712. Total amount information 2711 records the total amount of opticaldisc 10. Free area information 2712 records a free area (remaining area)of optical disc 10. Note that total amount information 2711 and freearea information 2712 are information to be printed, which will bedescribed in detail below. The hierarchical structure of lead-in area 27will be explained in more detail with reference to FIG. 9 to FIG. 11.

[0096] Information included in volume/file management information 70will be described with reference to FIG. 5.

[0097] Volume/file management information 70 includes a data recordingarea for recording rewrite count information 701. Rewrite countinformation 701 records the data rewrite count with respect to data areaDA. Note that rewrite count information 701 is information to beprinted, which will be described in detail below.

[0098] Information included in playback control information DA211 willbe described with reference to FIG. 6.

[0099] Playback control information DA211 includes a data recording areafor recording picture information INFO7. Picture information INFO7 isadditional data about moving picture data included in video object DA22.This additional data contains, e.g., recording date information INFO71,recording channel information INFO72, white balance information INFO73,zoom ratio information INFO74, shutter speed information INFO75, and GPSinformation INFO76. Note that these additional data are information tobe printed, which will be described in detail below.

[0100] Information included in menu index information INFO1 will bedescribed with reference to FIG. 7.

[0101] Menu index information INFO1 includes data recording areas forrecording start address data INFO11 and length data INFO12. Startaddress data INFO11 is data representing the start of an addressindicating the storage location of representative picture datacorresponding to a representative frame (to be described later). Lengthdata INFO12 is data representing a length from the address indicated bythe start address data. This means that representative picture data isstored between the address indicated by start address data INFO11 andthe address corresponding to the length indicated by length data INFO12.A combination of start address data INFO11 and length data INFO12indicates the storage location of representative picture data.

[0102] Information included in control information DA21 and video objectDA22 will be described with reference to FIG. 8.

[0103] Referring to FIG. 8, video manager VMG consists of a plurality offiles 74A. These files 74A describe information (video managerinformation VMGI, video object set VMGM_VOBS for video manager menus,and video manager information backup file VMGI_BUP) for managing videotitle sets (VTS#1 to VTS#n) 72.

[0104] Each video title set VTS 72 stores video data (video pack to bedescribed later) compressed by MPEG, audio data compressed by apredetermined format or uncompressed audio data (audio pack),runlength-compressed sub-picture data (sub-picture pack to be describedlater; including bitmap data, each pixel of which is defined by aplurality of bits), and also information for playing back these data(navigation pack to be described later; including presentation controlinformation PCI and data search information DSI).

[0105] Video title set VTS 72 is also made up of a plurality of files74B as in video manager VMG. Each file 74B contains video title setinformation VTSI, object set VTSM_VOBS for video title set menus, videoobject sets VTSTT_VOBS for video title set titles, and backupinformation VTSI_BUP for video title set information.

[0106] Note that the number of video title sets (VTS#1 to VTS#n) 72 islimited to a maximum of 99, and the number of files 74B that make upeach video title set VTS 72 is limited to a maximum of 12. These files74A and 74B are similarly split up at the boundaries of logical sectors.

[0107] Other recording area 73 can record information that can be usedin video title sets VTS 72 mentioned above or other kinds of informationthat do not pertain to video title sets. This area 73 is not mandatory,and may be deleted if it not used.

[0108] As will be described later-with reference to FIG. 11, each videoobject set VTSTT_VOBS for video title set titles defines a set of one ormore video objects VOB. Each VOB defines a set of one or more cells. Aset of one or more cells make up program chain PGC.

[0109] Assuming that one PGC corresponds to one drama, a plurality ofcells that make up this PGC can correspond to various scenes in thatdrama. The contents of the PGC (or those of cells) are adz determinedby, e.g., a software provider who produces the contents recorded on disc10.

[0110]FIG. 9 is a view for explaining information recorded on lead-inarea 27 of optical disc 10. When disc 10 is set in the DVD videorecorder to be described later (or DVD video player not shown),information on lead-in area 27 is read first. Lead-in area 27 records apredetermined reference code and control data in ascending order ofsector numbers.

[0111] The reference code in lead-in area 27 is made up of two errorcorrection code blocks (ECC blocks). Each ECC block consists of 16sectors. These two ECC blocks (32 sectors) are created by addingscramble data. Upon playing back the reference code added with thescramble data, filter operation or the like on the playback side is doneto play back a specific data symbol (e.g., 172), thus assuring data readprecision after that.

[0112] The control data in lead-in area 27 is made up of 192 ECC blocks.This control data field repetitively records the contents for 16 sectorsin each block 192 times. First one sector (2,048 bytes) constituting thecontrol data (16 sectors) in lead-in area 27 contains physical formatinformation, and the subsequent 15 sectors contain disc manufacturinginformation and contents provider information.

[0113] The contents of the physical format information will bedescribed.

[0114] The first byte position “0” describes the version of the DVDformat that the recorded information complies with.

[0115] The second byte position “1” describes the size (12 cm, 8 cm, orthe like) of a recording medium (optical disc 10) and minimum read-outrate. In case of a read-only DVD video, 2.52 Mbps, 5.04 Mbps, and 10.08Mbps are prescribed minimum read-out rates, but other minimum read-outrates are reserved. For example, when a DVD video recorder capable ofvariable bit rate recording records at an average bit rate of 2 Mbps,the minimum read-out rate can be set to fall within the range from 1.5to 1.8 Mbps using the reserve field.

[0116] The third byte position “2” describes the disc structure (thenumber of recording layers, track pitch, recording layer type, and thelike) of the recording medium (optical disc 10). Based on this recordinglayer type, disc 10 can be identified to be a DVD-ROM, DVD-R, or DVD-RAM(or DVD-RW).

[0117] The fourth byte position “3” describes the recording density(linear density & track density) of the recording medium (optical disc10). The linear density indicates the recording length per bit (0.267μm/bit, 0.293 μm/bit, or the like). On the other hand, the track densityindicates the neighboring track spacing (0.74 μm/track, 0.80 μm/track,or the like). The fourth byte position “3” also includes a reserve fieldto designate other numerical values as the linear density and trackdensity of a DVD-RAM or DVD-R.

[0118] The fifth byte position “4 to 15” describes the start and endsector numbers of data area 28 and the like of the recording medium(optical disc 10).

[0119] The sixth byte position “16” describes a burst cutting area (BCA)descriptor. This BCA is applied as an option to a DVD-ROM disc alone,and is an area for storing recorded information upon completion of thedisc manufacturing process.

[0120] The seventh byte position “17 to 20” describes a free space orfree area of the recording medium (optical disc 10). For example, whendisc 10 is a single-sided recording DVD-RAM disc, information indicating2.6 GB (or the number of sectors corresponding to this number of bytes)is stored at that position of disc 10. On the other hand, when disc 10is a double-sided recording DVD-RAM disc, information indicting 5.2 GB(or the number of sectors corresponding to this number of bytes) isstored at that position.

[0121] The eighth and ninth byte positions “21 to 31” and “32 to 2,047”are reserved for the future.

[0122]FIG. 10 exemplifies the directory structure of information (datafiles) recorded on optical disc 10. As in the hierarchical filestructure used by a versatile operation system of a computer, thesubdirectory of video title set VTS and that of audio title set ATS aremade under the root directory. Various video files (files VMGI, VMGM,VTSI, VTSM, VTS, and the like) are allocated in the subdirectory ofvideo title set VTS to manage the individual files systematically. Aspecific file (e.g., specific VTS) can be accessed by designating thepath from the root directory to that file.

[0123] DVD-RAM (DVD-RW) disc 10 or DVD-R disc 10 shown in FIG. 1 may bepre-formatted to have the directory structure shown in FIG. 10, andpre-formatted discs 10 may be put on the market as unused discs (rawdiscs) for DVD video recording.

[0124] That is, the root directory of pre-formatted raw disc 10 includesa subdirectory named a video title set (VTS). This subdirectory cancontain various management data files (VIDEO_TS.IFO, VTS_01_0.IFO);backup files (VIDEO_TS.BUP, VTS_01_0.BUP) for backing up information ofthese management data files; and a video data file (VTS_01_1.VOB) whichis managed based on the contents of the management data files and storesdigital moving picture information.

[0125] The subdirectory can also contain menu data files (VMGM, VTSM)for storing predetermined menu information.

[0126] The contents of a directory record corresponding to the directorystructure shown in FIG. 10 will be described.

[0127] The first relative byte position “0” describes the directoryrecord length.

[0128] The second relative byte position “1” describes the record lengthof an assigned extent attribute.

[0129] The third relative byte position “2” describes the first logicalsector number assigned to an extent.

[0130] The fourth relative byte position “10” describes the data lengthof the file field.

[0131] The fifth relative byte position “18” describes the recordingdata/time of information in the extent described in the directoryrecord. Data at the relative byte position “18” can be used forrecording the recording data/time of a recorded program (correspondingto specific VTS) in the DVD video recorder.

[0132] The sixth relative byte position “25” describes a file flagindicating the characteristics of files defined in Table 10 of ISO9660.

[0133] The seventh relative byte position “25” describes the file unitsize assigned to the file field.

[0134] The eighth relative byte position “27” describes the interleavedgap size assigned to the file field.

[0135] The ninth relative byte position “28” describes the volumesequence number in the volume set on the extent described in thedirectory record.

[0136] The 10th relative byte position “32” describes the file ID fieldlength of the directory record.

[0137] The 11th relative byte position “33” describes the file ID or thedirectory defined by ISO9660.

[0138] Next to the file ID, a padding field serving as stuffing when thefile ID field has an even-byte length is described.

[0139] Next to the padding field, copyright management information usedby the system is described.

[0140] After the copyright management information, a read flag (orplayed back flag) indicating whether or not a specific recorded file(e.g., VTS_01_1.VOB in FIG. 10) has been read out once (or that VTS hasbeen played back at least once previously) is described. The read flagfor a file which is not yet read out is set at “0”. If the file has beenread out at least once, the read flag of that file is set at “1”.

[0141] Next to the read flag, an archive flag (or permanent keep flag)indicating whether or not a specific recorded file (e.g., VTS_01_1.VOBin FIG. 10) has contents to be kept permanently (or contents that areprevented from being erroneously erased or deleted) is described. Thearchive flag for a file which can be erased is set at “0”. The archiveflag for a file which is to be kept permanently without being erased isset at “1”.

[0142]FIG. 11 shows the hierarchical structure of information containedin video object set VTSTT_VOBS shown in FIG. 8.

[0143] As shown in FIG. 11, each cell 84 consists of one or more videoobject units (VOBU) 85. Each video object unit 85 is constituted as aset (pack sequence) of video packs (V packs) 88, sub-picture packs (SPpacks) 90, and audio packs (A packs) 91 to have navigation pack (NVpack) 86 at the beginning of the sequence. That is, video object unitVOBU 85 is defined as a set of all packs recorded from certainnavigation pack 86 to a pack immediately before the next navigation pack86.

[0144] Each of these packs serves as a minimum unit for data transfer.The minimum unit for logical processing is a cell, and logicalprocessing is done in units of cells.

[0145] Navigation pack 86 is built in each video object unit VOBU 85 torealize both angle changes (non-seamless playback and seamlessplayback).

[0146] The playback time of video object unit VOBU 85 corresponds tothat of video data made up of one or more picture groups (groups ofpictures; to be abbreviated as GOPs) included in video object unit VOBU85, and is set to fall within the range from 0.4 sec to 1.2 sec. One GOPis screen data which normally has a playback time of about 0.5 sec inthe MPEG format, and is compressed to play back approximately 15 imagesduring this interval.

[0147] When video object unit VOBU 85 includes video data, a videodatastream is formed by arranging GOPs (complying with MPEG) eachconsisting of video packs 88, sub-picture packs 90, and audio packs 91.However, independently of the number of GOPs, video object unit VOBU 85is defined with reference to the playback time of GOPs, and navigationpack 86 is always set at the beginning of unit 85, as shown in FIG. 11.

[0148] Even playback data consisting of audio data and/or sub-picturedata alone is formed using video object unit VOBU 35 as one unit. Forexample, when video object unit VOBU 85 is formed by audio packs 91alone to have navigation pack 86 at its beginning, audio packs 91 to beplayed back in the playback time of video object unit VOBU 85 to whichthe audio data belong are stored in that video object unit VOBU 85 as invideo object VOB 83 of video data.

[0149] When a DVD video recorder can record video title set VTScontaining VOBSs 82 with the structure shown in FIG. 11 on optical disc10, the user often wants to edit the recording contents after the VTS isrecorded. In order to meet such requirement, dummy packs 89 can beappropriately inserted in each VOBU 85. Each dummy pack 89 can be usedfor recording edit data later.

[0150] As shown in FIG. 11, video object set (VTSTT_VOBS) 82 is definedas a set of one or more video objects (VOB) 83. Video objects VOB 83 invideo object set VOBS 82 are used for the same purpose.

[0151] VOBS 82 for menus normally consists of one VOB 83, which stores aplurality of menu screen display data. By contrast, VOBS 82 for a titleset normally consists of a plurality of VOBs 83.

[0152] Taking a concert video title of a certain rock band as anexample, VOBs 83 that form video object set VTSTT_VOBS 82 for a titleset correspond to picture data of the performance of that band. In thiscase, by designating given VOB 83, for example, the third tune in theconcert of the band can be played back.

[0153] VOB 83 that forms video object set VTSM_VOBS for menus storesmenu data of all the tunes performed in the concert of the band, and aspecific tune, e.g., an encore, can be played back according to the menudisplay.

[0154] Note that one VOB 83 can form one VOBS 82 in a normal videoprogram. In this case, a single video stream comes to an end in one VOB83.

[0155] On the other hand, in case of a collection of animations having aplurality of stories or an omnibus movie, a plurality of video streams(a plurality of video chains PGC) can be set in single VOB 82 incorrespondence with the respective stories. In this case, the individualvideo streams are stored in corresponding VOBS 83. An audio stream andsub-picture stream pertaining to each video stream end in correspondingVOB 83.

[0156] VOBs 83 are assigned identification numbers (IDN#i; i=0 to i),and that VOB 83 can be specified by the identification number. VOB 83consists of one or more cells 84. A normal video stream consists of aplurality of cells, but a video stream for menus often consists ofsingle cell 84. Cells 84 are assigned identification numbers (C_IDN#j)as in VOBs 83.

[0157]FIG. 12 exemplifies a data sequence (pack sequence) in the packformat, which is obtained after data recorded on optical disc 10 areread out, and are subjected to signal demodulation/error correction in adisc drive (not shown). This pack sequence includes navigation pack(control pack) 86, video packs 88, dummy packs 89, sub-picture packs 90,and audio packs 91. All these packs consist of data in units of 2 kbytesas in the logical sectors shown in FIG. 2B.

[0158] Navigation pack 86 includes pack header 110, playback controlinformation/presentation control information (PCI) packet 116, and datasearch information (DSI) packet 117. PCI packet 116 is made up of packetheader 112 and PCI data 113, and DSI packet 117 of packet header 114 andDSI data 115. PCI packet 116 contains control data used upon switchingthe non-seamless angles, and DSI packet 117 contains control data usedupon switching the seamless angles.

[0159] Note that the angle switching means changes in angle (cameraangle) of watching the object picture. In case of a rock concert videotitle, for example, the user can watch scenes from various angles, e.g.,a scene that mainly captures a vocalist, a scene that mainly captures aguitarist, a scene that mainly captures a drummer, and the like in aperformance scene of an identical tune (identical event).

[0160] The angle is switched (changed) when the viewer can select anglesin accordance with his or her favor, and when an identical sceneautomatically repeats itself with different angles in the flow of story(if the software producer/provider has programmed the story in such way;or if the user of the DVD video recorder edits in such way).

[0161] The angles are set in the following cases: temporallydiscontinuous, non-seamless playback that presents and identical sceneof different angles (for example, in a scene at the instance when acertain boxer throws a counterpunch, the camera angle is changed toanother angle to play back a scene in which the counterpunch begins tobe thrown), and temporally continuous, seamless playback that changesthe angle between temporally continuous scenes (for example, at theinstance when a certain boxer has made a counterpunch, the camera angleis changed to another angle to play back a scene in which the otherboxer who got the punch is blown off).

[0162] Video pack 88 is comprised of pack header 881 and video packet882. Dummy pack 89 is comprised of pack header 891 and padding packet890, and padding packet 890 of packet header 892 and padding data 893.Note that padding data 893 stores insignificant data.

[0163] Sub-picture pack 90 is made up of pack header 901 and sub-picturepacket 902. Audio pack 91 is made up of pack header 911 and audio packet912.

[0164] Note that video packet 882 in FIG. 12 contains a packet header(not shown), which records a decode time stamp (DST) and presentationtime stamp (PTS). Each of sub-picture packet 902 and audio packet 912contains a packet header (not shown), which records a presentation timestamp (PTS).

[0165] Subsequently, the data structure for one navigation pack will bedescribed.

[0166] More specifically, one navigation pack 86 consists of 2,010 bytenavigation data including 14 byte pack header 110, 24 byte system header111, and two packets (116, 117). The two packets that form thenavigation data are presentation control information (PCI) packet 116and data search information (DSI) packet 117 in the description of FIG.12.

[0167] PCI packet 116 consists of 6 byte packet header 112A, 1 bytesubstream identifier (substream ID) 112B, and 979 byte PCI data 113. Thedatastream of PCI data 113 is designated by an 8 bit code “00000000” ofsubstream ID 112B.

[0168] DSI packet 117 is constructed by 6 byte packet header 114A, 1byte substream identifier (substream ID) 114B, and 1,017 byte DSI data115. The datastream of DSI data 115 is designated by an 8 bit code“00000001” of substream ID 114B.

[0169] The data length for one navigation pack 86 with the abovestructure is 2,048 bytes (2 kbytes) corresponding to one logical sectorshown in FIG. 2B.

[0170] Pack header 110 and system header 111 are defined by the MPEG2system layer. More specifically, pack header 110 stores information suchas a pack start code, system clock reference (SCR), and multiplexingrate, and system header 111 describes a bit rate and stream ID.Likewise, packet header 112A of PCI packet 116 and packet header 114A ofDSI packet 117 each store a packet start code, packet length, and streamID, as defined by the MPEG2 system layer.

[0171] The structure for one dummy pack will be described. That is, onedummy pack 89 is made up of pack header 891, packet header 892 with apredetermined stream ID, and padding data 893 padded with apredetermined code. (Packet data 892 and padding data 893 form paddingpacket 890). The contents of padding data 893 in a non-used dummy packare not especially significant. This dummy pack 89 can be appropriatelyused when the recording contents are to be edited after predeterminedrecording is done on disc 10.

[0172] For example, a case will be examined below wherein the contentsof a video tape that recorded a family trip using a portable videocamera are recorded and edited on DVD-RAM (or DVD-RW) disc 10.

[0173] In this case, only the video scenes to be stored in a single discare selectively recorded on disc 10. These video scenes are recorded invideo pack 88 shown in FIG. 11. Also, audio data simultaneously recordedby the video camera is recorded in audio pack 91.

[0174] Each VOBU 85 that includes video pack 88 and the like hasnavigation pack 86 at its beginning. As shown in FIG. 12, thisnavigation pack 86 contains presentation control information PCI anddata search information DSI. Using this PCI or DSI, the playbackprocedure of each VOBU can be controlled (for example, discontinuousscenes can be automatically connected or a multiangle scene can berecorded).

[0175] After the contents of the video tape are edited and recorded ondisc 10, when a voice, effect sound, and the like are to be postrecorded(or after-recorded) in each scene in units of VOBU or a background music(BGM) is added, such postrecording (or after-recording) audio data orBGM can be recorded in dummy pack 89. When a comment for the recordedcontents is to be added, sub-pictures such as additional characters,figures, and the like can be recorded in dummy pack 89. Furthermore,when an additional video picture is to be inserted, the inserted videopicture can be recorded in dummy pack 89.

[0176] The above-mentioned postrecording (or after-recording) audio dataor the like is written in padding data 893 of dummy pack 89 used as anaudio pack. The additional comment is written in padding data 893 ofdummy pack 89 used as a sub-picture pack. Similarly, the inserted videopicture is written in padding data 893 of dummy pack 89 used as a videopack. Incidentally, when the postrecording (after-recording) ispredetermined, silent audio data coded in the same manner as theoriginal audio data can be written in the dummy pack. In this case, theoriginal audio data may be recorded as a first stream, and the silentaudio data may be recorded as a second stream.

[0177] More specifically, dummy pack 89 is a wildcard pack that canbecome any of an audio, sub-picture, and video packs depending on itspurpose.

[0178]FIG. 13 shows PCI packet 116 included in navigation pack 86located at the beginning of each VOBU 85. As shown in FIG. 13, PCIpacket 116 includes presentation control information PCI (PCI data) 113as navigation data used for changing the display or playback contents(presentation contents) in synchronism with the playback state of videodata in video object unit (VOBU) 85.

[0179] The contents of presentation control information (PCI data) 113will be described. PCI data 113 includes 60 byte PCI general information(PCI_GI), 36 byte non-seamless playback angle information (NSML_AGLI),694 byte highlight information (HLI), and 189 byte recording information(RECI). This recording information (RECI) can contain a copyrightmanagement code (ISRC) of the international standard.

[0180] Highlight information HLI is used upon execution of the followinghighlight processing. More specifically, the MPU (or CPU) of the DVDvideo recorder (to be described later) reads highlight information HLI,and detects the X-/Y-coordinate values, colors, contrast values, and thelike of rectangular regions (highlight buttons) displayed by sub-picturedata. The MPU of the DVD video recorder highlights the displayed menuselection item and the like in accordance with these detected data. Thishighlight processing is used as a means for allowing the user to easilyrecognize a specific displayed item on the visual user interface. Morespecifically, when a D video title recorded on optical disc 10 is amultilingual compatible program, a specific spoken language (e.g.,English) and a specific superimposed dialogue language (e.g., Japanese)are selected by highlight buttons which are displayed to be visuallyoutstanding by the highlight processing.

[0181] The contents of general information PCI_GI of this PCI will bedescribed.

[0182] Presentation control information general information PCI_GIdescribes the logical block number (NV_PCK_LBN) of a navigation pack,the category (VOBU_CAT) of a video object unit (VOBU), user operationcontrol (VOBU_UOP_CTL) of the video object unit (VOBU), the startpresentation time (VOBU_S_PTM) of the video object unit (VOBU), the endpresentation time (VOBU_E_PTM) of the video object unit (VOBU), the endpresentation time (VOBU_SE_PTM) of the sequence end in the video objectunit (VOBU), and a cell elapse time (C_ELTM).

[0183] Note that the logical block number (NV_PCK_LBN) represents theaddress (recording location) of a navigation pack including thepresentation control information (PCI) by the relative number of blocksfrom the first logical block in the video object set (VOBS) whichincludes that PCI.

[0184] The category (VOBU_CAT) describes the contents of copy protectionof an analog signal corresponding to video and sub-picture data in thevideo object unit (VOBU) that includes the presentation controlinformation (PCI).

[0185] The user operation control (VOBU_UOP_CTL) describes useroperations which are prohibited during the display (presentation) periodof the video object unit (VOBU) that includes the presentation controlinformation (PCI).

[0186] The start presentation time (VOBU_S_PTM) describes the start timeof display (presentation) of the video object unit (VOBU) that includesthe presentation control information (PCI). More specifically, thisVOBU_S_PTM indicates the start display time of the first video (firstpicture) in the display order of the first GOP in the video object unit(VOBU).

[0187] The end presentation time (VOBU_E_PTM) describes the end time ofdisplay (presentation) of the video object unit (VOBU) that includes thepresentation control information (PCI). More specifically, when thevideo object unit (VOBU) includes continuous video data, this VOBU_E_PTMindicates the end display time of the last video (last picture) in thedisplay order of the last GOP in the video object unit (VOBU).

[0188] On the other hand, when no video data is present in the videoobject unit (VOBU), or when playback of that video object unit (VOBU) isstopped, this VOBU_E_PTM indicates the end time of virtual video dataaligned to the time grids at a field interval (1/60 sec in case of NTSCvideo).

[0189] The end presentation time (VOBU_SE_PTM) describes the end time ofdisplay (presentation) based on a sequence end code in video data in thevideo object unit (VOBU) that includes the presentation controlinformation (PCI). More specifically, this end time indicates the enddisplay time of the last video (last picture) in the display order,which picture includes the sequence end code, in the video object unit(VOBU). If no video (picture) with a sequence end code is present in thevideo object unit (VOBU), 00000000h (h is an abbreviation forhexadecimal) is set in VOBU_SE_PTM.

[0190] The cell elapse time (C_ELTM) describes the relative display(presentation) time from the first video frame in the display order of acell that includes the presentation control information (PCI) to thefirst video frame in the display order of the video object unit (VOBU)that includes the PCI in hours, minutes, and seconds in the BCD formatand frames. When no video data is present in the video object unit(VOBU), the first video frame of the virtual video data is used as thevideo frame.

[0191]FIG. 14 shows the contents of video manager VMG shown in FIG. 8.This VMG consists of a plurality of files 74A. Video manager VMGincludes video manager information (VMGI) 75, object set (VMGM_VOBS) forvideo manager menus, and backup (VMGI_BUP) of video manager informationin correspondence with each file.

[0192] Note that video manager information VMGI and backup VMGI_BUP ofvideo manager information are mandatory items, and video object setVMGM_VOBS for displaying video manager information menu VMGM isoptional.

[0193] As shown in FIG. 14, video manager information (VMGI) 75 set atthe beginning of video manager VMG describes a video manager informationmanagement table (VMGI_MAT; mandatory), title search pointer table(TT_SRPT; mandatory), video manager menu program chain information unittable (VMGM_PGCI_UT; mandatory when VMGM_VOBS exists), parentalmanagement information table (PTL_MAIT; option), video title setattribute table (VTS_ATRT; mandatory), text data manager (TXTDT_MG;option), video manager menu cell address table (VMGM_C_ADT; mandatorywhen VMGM_VOBS exists), and video manager menu video object unit addressmap (VMGM_VOBU_ADMAP; mandatory when VMGM_VOBS exists) in this order.

[0194] Note that the addresses such as an end address (VMGI_MAT_EA) ofvideo manager information management table VMGI_MAT, a start address(TT_SRPT_SA) of title search pointer TT_SRPT, and the like are describedas the relative number of logical blocks from the head logical blockthat stores this table VMGI_MAT.

[0195] Video manager information (VMGI) 75 contains information usedupon playing back each video title set (VTS) 72 shown in FIG. 8, andsuch information is recorded on optical disc 10 to match the logicalsector boundary.

[0196] Video manager information menu video object set VMGM_VOBS storesmenu information (managed by video manager VMG) which pertains to videodata, audio data, and sub-picture data recorded on optical disc 10.

[0197] With this video manager information menu video object set(VMGM_VOBS), the volume name of the optical disc to be played back, andaudio and sub-picture comments upon displaying the volume name can bedisplayed. Also, selectable items can be displayed as sub-picture data.

[0198] For example, video manager information menu video object set(VMGM_VOBS) allows to display a comment indicating that the optical discto be played back contains a video (in a single story or multi-storyformat) of the road to the world champion of given boxer X assub-picture data. That is, the fighting pose of boxer X is played backas video data together with the volume name such as “glorious history ofboxer X” or the like, high theme (if any) is output as audio data, andthe chronological table of his career/records and the like are displayedas sub-picture data.

[0199] Also, as the selection items displayed as sub-picture data byVMGM video object set (VMGM_VOBS), (1) an inquiry as to whether anarration voice of the match is played back in English, Japanese,French, German, and the like, (2) an inquiry as to whether or not asuperimposed dialog in a predetermined language is displayed assub-picture data, and (3) an inquiry as to which one of a plurality ofselectable language superimposed dialogs is selected, are output. Theviewer (the user of the DVD video recorder; to be described later) canselect English as the narration voice and Japanese as the sub-picturesuperimposed dialog from the displayed items by the VMGM video objectset (VMGM_VOBS). In this way, the user is ready to watch the video ofthe match of boxer X.

[0200] The above-mentioned features such as comments of the recordingcontents using sub-picture data and/or audio data, arbitrary selectionof a spoken language and superimposed dialog language, and theaforementioned playback angle changes are not available in aconventional video recorder (VHS VCR or the like), but the DVD videorecorder of the present invention can have such features.

[0201]FIG. 15 shows the contents of video manager information managementtable VMGI_MAT shown in FIG. 14.

[0202] More specifically, video manager information management tableVMGI_MAT describes a video manager identifier (VMG_ID); the end address(VMG_EA) of the video manager; the end address (VMGI_EA) of videomanager information; a version number (VERN) of the format that opticaldisc (DVD disc) 10 of interest uses; a video manager category (VMG_CAT);a volume set identifier (VLMS_ID); free space (recordable amount)FREE_SPACE of optical disc 10 on which video title sets VTS shown inFIG. 8 are recorded; the number of videotitle sets (VTS_Ns); a provider(a software producer/distributor) unique identifier (PVR_ID); the endaddress (VMGI_MAT_EA) of the video manager information management table;the start address (FP_PGCI_SA) of first play program chain information;the start address (VMGM_VOBS_SA) of the video manager menu video objectset; the start address (TT_SRPT_SA) of the title search pointer table;the start address (VMGM_PGCI_UT_SA) of the video manager menu programchain information unit table; the start address (PTL_MAIT_SA) of theparental management information table; the start address (VTS_ATRT_SA)of the video title set attribute table; the start address (TXTDT_MG_SA)of the text data manager; the start address (VMGM_C_ADT_SA) of the videomanager menu cell address table; the start address (VMGM_VOBU_ADMAP_SA)of the video manager menu video object unit address map; a videoattribute (VMGM_V_ATR) indicated by the video manager menu; the numberof audio streams (VMGM_AST_Ns) indicated by the video manager menu; anaudio stream attribute (VMGM_AST_ATR) indicated by the video managermenu; the number of sub-picture streams (VMGM_SPST_Ns) indicated by thevideo manager menu; a sub-picture stream attribute (VMGM_SPST_ATR)indicated by the video manager menu; and first play program chaininformation (FP_PGCI).

[0203] Note that video manager category VMG_CAT of video managerinformation management table VMGI_MAT describes video copy flags andaudio copy flags of the video manager and video title sets. Depending onthe contents of these flags, whether or not video and audio data can becopied are independently determined.

[0204] Free space (recordable amount) FREE_SPACE shown in FIG. 15 equalsfree space data in the physical format information. The free space ofdisc 10 may be stored in either a file descriptor (physical formatinformation) or management information (VMGI_MAT). The disc free spaceafter disc 10 is partially recorded can be written in FREE_SPACE in FIG.15 and/or the free space field of the physical format information (inthis case, that data is written in both FREE_SPACE and physical formatinformation).

[0205] For example, in case of single-sided DVD-RAM disc 10 having astorage amount of 2.6 GB, information indicating 2.6 GB is written inthe free space of the physical information. If no data is recorded onthis disc 10 at all, information indicating a value obtained Hbysubtracting management data (including video manager VMG) and the likefrom 2.6 GB is written in FREE_SPACE in FIG. 15.

[0206] If recording for 1 GB has been done on this disc 10, informationstored in the free space field of the physical format information isequivalent to 2.6 GB, but information in FREE_SPACE in FIG. 15 isrewritten to that indicating 1.6 GB or equivalent. When such partiallyrecorded disc 10 is set in the DVD video recorder (to be describedlater), the DVD video recorder initially reads the information in thefree space field of the physical format information to detect that setdisc 10 is a 2.6 GB disc, and then reds the information in FREE_SPACE inFIG. 15 to detect that the free space of set disc 10 is 1.6 GB. If allthe data on this disc 10 are erased, the contents of FREE_SPACE in FIG.15 and information in the free space field of the physical formatinformation in FIG. 15 are rewritten to indicate 2.6 GB or equivalent.

[0207] That is, upon expressing “free space”, the free space field ofthe physical format information and FREE_SPACE in FIG. 15 can havedifferent contents.

[0208]FIG. 16 shows the contents of video title set VTS 72 in FIG. 8.Video title set VTS consists of a plurality of files 74B as in videomanager VMG shown in FIG. 14. Each file 74B contains video title setinformation (VTSI) 94, object set (VTSM_VOBS) for video title set menus,video object sets (VTSTT_VOBS; nine files in maximum) for video titleset titles, and backup information (VTSI_BUP) for video title setinformation.

[0209] As shown in FIG. 16, video title set information VTSI 94 set atthe beginning of video title set VTS 72 describes a video title setinformation management table (VTSI_MAT; mandatory), a title searchpointer table (VTS_PTT_SRPT; mandatory) for a video title setpart_of_title (e.g., chapter of a program), a video title set programchain information table (VTS_PGCIT; mandatory), a video title set menuprogram chain information unit table (VTSM_PGCI_UT; mandatory whenVTSM_VOBS exists), a video title set time map table (VTS_TMAPT; option),a video title set menu cell address table (VTSM_C_ADT; mandatory whenVTSM_VOBS exists), a video title set menu video object unit address map(VTSM_VOBU_ADMAP; mandatory when VTSM_VOBS exists), a video title setcell address table (VTS_C_ADT; mandatory), and a video title set videoobject unit address map (VTS_VOBU_ADMAP; mandatory) in this order.

[0210]FIG. 17 shows the contents of video title set informationmanagement table VTSI_MAT shown in FIG. 16.

[0211] As shown in FIG. 17, this video title set information managementtable VTSI_MAT describes a video title set identifier (VTS_ID), the endaddress (VT_EA) of the video title set, a played back flag (PLAY_ENDFlag) indicating whether or not a program (e.g., VTS#1 in FIG. 8)recorded on optical disc 10 has been completely played back at leastonce, an archive flag (ARCHIVE Flag) which serves to prevent eraseerrors when a program (e.g., VTS#2 in FIG. 8) recorded on optical disc10 is to be kept without being erased, the end address (VTSI_EA) ofvideo title set information, a version number (VERN) of the format thatthis optical disc (DVD disc) 10 uses, a video title set category(VTS_CAT), the end address (VTSI_MAT_EA) of the video title setinformation management table, the start address (VTSM_VOBS_SA) of thevideo title set menu video object set, the start address (VTSTT_VOBS_SA)of the video title set title video object set, the start address of(VTS_PTT_SRPT_SA) of the video title set part_of_title search pointertable, the start address (VTS_PGCIT_SA) of the video title set programchain information table, the start address (VTSM_PGCI_UT_SA) of thevideo title set menu program chain information unit table, the startaddress (VTS_TMAPT_SA) of the video title set time map table, the startaddress (VTSM_C_ADT_SA) of the video title set menu cell address table,the start address (VTSM_VOBU_ADMAP _SA) of the video title set menuvideo object unit address map, the start address (VTS_C_ADT_SA) of thevideo title set cell address table, the start address(VTS_VOBU_ADMAP_SA) of the video title set video object unit addressmap, information of attributes of video data, audio data, sub-picturedata, and the like, the number of sub-picture streams (VTS_SPST_Ns) ofthe video title set, a sub-picture stream attribute table(VTS_SPST_ATRT) of the video title set, and a multichannel audio streamattribute table (VTS_MU_AST_ATRT) of the video title set.

[0212] Note that the respective information items of table VTSM_MAT arealigned to the logical block boundaries of data recorded on optical disc10.

[0213] The contents of video title set program chain information tableVTS_PGCIT shown in FIG. 16 will be described.

[0214] As shown in FIG. 16, this video title set program chaininformation table VTS_PGCIT contains video title set program chaininformation table information (VTS_PGCITI), video title set programchain information search pointers (VTS_PGCI_SRP#1 to VTS_PGCI_SRP#n),and video title set program chain information (VTS_PGCI).

[0215] Note that the order of a plurality of pieces of video title setprogram chain information VTS_PGCI is set independently of that of theplurality of video title set program chain information search pointersVTS_PGCI_SRP#1 to VTS_PGCI_SRP#n. Hence, for example, single programchain information VTS_PGCI can be indicated by one or more program chaininformation search pointers VTS_PGCI_SRP.

[0216] The contents of video title set program chain informationVTS_PGCI shown in FIG. 16 will be described. That is, program chaininformation (PGCI) is made up of program chain general information(PGC_GI; mandatory), a program chain command table (PGC_GI; mandatory),program chain general information (PGC_CMDT; option), a program chainprogram map (PGC_CMAP; mandatory when C_PBIT to be described belowexists), a cell playback information table (C_PBIT; option), and a cellposition information table (C_POSIT; mandatory when C_PBIT aboveexists).

[0217] The contents of cell playback information table C_PBIT will bedescribed. Cell playback information table C_PBIT contains a maximum of255 pieces of cell playback information (C_PBI#1 to C_PBI#n).

[0218] The contents of cell playback information C_PBI (C_PBI#1 toC_PBI#n) will be described. Each cell playback information (C_PBI)includes a cell category (C_CAT; 4 bytes), cell playback time (C_PBTM; 4bytes), the start address (C_FVOBU_SA; 4 bytes) of the first videoobject unit (VOBU) in the cell, the end address (C_FILVUJ_EA; 4 bytes)of the first interleaved unit (ILVU) in the cell, the start address(C_LVOBU_SA; 4 bytes) of the last video object unit (VOBU) in the cell,and the end address (C_LVOBU_EA; 4 bytes) of the last video object unit(VOBU) in the cell.

[0219] Especially, in this C_PBI, a 1 byte field for setting an eraseprohibition flag is assured at a relative byte position (RBP). When “0”is described in this erase prohibition flag field, data can be freelyerased; when “1” is described, data is to be permanently kept. Thisdescription can be freely made by the user.

[0220] The contents of the aforementioned cell category C_CAT will bedescribed. The cell category (C_CAT) indicates the number of cellcommands by the lower 8 bits (b0 to b7); the cell still time by the next8 bits (b8 to bl5); the cell type (e.g., karaoke) by the next 5 bits(b16 to b20); an access restriction flag by the next 1 bit (b21); thecell playback mode (e.g., movie or still) by the next 1 bit (b22); aseamless angle change flag by 1 bit (b24) after the next reserved bit; asystem time clock (STC) discontinuity flag (to reset STC or not) by thenext 1 bit (b25); an interleaved allocation flag (indicating if the celldesignated by C_PBI is located in a continuous block or an interleavedblock) by the next 1 bit (b26); a seamless playback flag (indicating ifthe cell designated by C_PBI is to be played back seamlessly) by thenext 1 bit (b27); the cell block type (e.g., angle block) by the nexttwo bits (b28 and b29); and the cell block mode (e.g., first cell in theblock) by the last two bits (b30 and b31).

[0221] If the cell block mode bits are 00b (b means binary), this meansthat the cell is not the one in the block; if the bits are 01b, the cellis the first one in the block; if the bits are 10b, the cell is the onein the block; and if the bits are 11b, the cell is the last one in theblock.

[0222] If the cell block type bits are 00b, this indicates that the cellblock does not belong to the corresponding block; and if the bits are01b, the corresponding block is an angle block (a block containingmultiangle cells).

[0223] If the cell block type bits are not 01b during playback of atitle containing multiangle cells, for example, an angle mark (notshown) is kept ON.

[0224] On the other hand, if this cell block type=01b is detected duringplayback, the DVD video recorder can inform the viewer that playback ofthe angle block is currently in progress by flickering the angle mark(not shown; or by changing the ON color or shape of the angle mark).With such information, the viewer can make sure that an image in anotherangle pertaining to the picture which is currently being played back isavailable.

[0225] If the interleaved allocation flag is 0b, it indicates that thecorresponding cell belongs to a continuous block (that continuouslyrecords a plurality roe of VOBUs); if the interleaved allocation flag is1b, the corresponding cell belongs to an interleaved block (thatinterleaved-records ILVUs each containing one or more VOBUS).

[0226] If the seamless angle change flag is set (=1b), it representsthat the corresponding cell is to be seamlessly played back; if thisflag is not set (=0b), the corresponding cell is to be non-seamlesslyplayed back.

[0227] That is, if the interleaved allocation flag=1b and seamless anglechange flag=0b, the angle can be changed non-seamlessly; if theinterleavhed allocation flag=1b and seamless angle change flag=1b, theangle can be changed seamlessly.

[0228] If a media drive system with a very short access time (a systemthat can access the beginning of a desired angle block within one videoframe period; not limited to an optical disc drive system) is used, theangle can be changed smoothly even when the interleaved allocationflag=0b, i.e., between VOBU sets (different angle cells) which are notinterleaved-recorded.

[0229] When optical disc 10 with relatively low access speed is used asa recording medium, one recording track of that disc is preferablyassigned to recording of one interleaved block. In such format, sincethe trace destination of an optical head need only move in the radialdirection of the disc by a very small distance corresponding to onetrack width, track jump suffering less time lag (suitable for seamlessangle change) can be attained. In this case, if track jump for one videoobject unit (VOBU) is made, a time lag for a maximum of one revolutionof the disc may be produced. Hence, the angle change that requires jumpsin units of VOBUs is suitable for non-seamless angle change.

[0230] Note that the contents of the seamless angle change flag arenormally determined in advance by the provider (the software producerwho produces the program contents of titles recorded on DVD disc 10).That is, by determining the contents of the seamless angle change flagin advance, the provider can uniquely determine whether the non-seamlessangle change or seamless angle change is to be used.

[0231] However, it is technically possible to design the DVD videorecorder which allows the viewer (the user of the DVD video recorder tobe described later) to arbitrarily change the contents of the seamlessangle change flag in read data after cell data of the correspondingtitle set are read from the optical disc.

[0232] Since the seamless angle change flag represents whether the angleinformation described in navigation pack 86 indicates seamless ornon-seamless angle information, if the user has changed this flag, he orshe should modify angle information (not shown) in navigation pack 86(e.g., modification from seamless angle information to non-seamlessangle information). In this case, the arrangement of packs constitutingthe angle should also be modified, accordingly.

[0233] When the cell playback mode is 0b, it indicates continuousplayback in the cell; if the mode is 1b, still playback in each VOBUpresent in the cell.

[0234] When the user makes recording, playback, and the like, the accessrestriction flag can be used upon prohibiting direct selection by useroperation. For example, when the access restriction flag of a cell thatrecords answers for a collection of questions, the user is prohibitedfrom reading the answers by stealth.

[0235] The cell type can indicate the following ones by its 5 bitcontents, for example, when the corresponding cell is formed forkaraoke.

[0236] If the 5 bits are 00000b, no cell type is designated; if the 5bits are 00001b, a title image of the karaoke is designated; if the 5bits are 00010b, an introduction part of the karaoke is designated; ifthe 5 bits are 00011b, a song part other than a climax (bridge) part isdesignated; if the 5 bits are 00100b, a song part of the first climaxpart is designated; if the 5 bits are 00101b, a song part of the secondclimax part is designated; if the 5 bits are 00110b, a song part for amale vocal is designated; if the 5 bits are 00111b, a song part for afemale vocal is designated; if the 5 bits are 01000b, a song part formixed voices is designated; if the 5 bits are 01001b, an interlude part(instrumental part) is designated; if the 5 bits are 01010b, fading-inof the interlude part is designated; if the 5 bits are 01011b,fading-out of the interlude part is designated; if the 5 bits are01100b, the first ending part is designated; and if the 5 bits are01101b, the second ending part is designated. The contents of theremaining 5 bit code can be used for other purposes.

[0237] Note that the angle change can be applied to that for backgroundvideo data of karaoke. (For example, a full-figure shot, closeup shotsof the face and mouth, and the like of a singer who is singing a guidevocal can be angle-changed seamlessly along with the flow of a karaokemusic or non-seamlessly by going back some bars, or during repeatplayback between desired bars, as the viewer desired.)

[0238] On the other hand, if the 8 bit contents of the cell still timeare 00000000b, zero still time is designated; if the contents are11111111b, limitless still time is designated; if the contents fallwithin the range from 00000001b to 11111110b, a still display timehaving a duration defined by the decimal value (1 to 254) designated bythe contents and expressed in seconds is designated.

[0239] The number of cell commands indicates the number of commands tobe executed upon completion of playback of the corresponding cell.

[0240]FIG. 18 shows the contents of program chain general informationPGC_GI.

[0241] As shown in FIG. 18, program chain general information PGC_GIdescribes program chain contents (PGC_CNT), a program chain playbacktime (PGC_PB_TM), program chain user operation control information(PGC_UOP_CTL), a program chain audio stream control table(PGC_AST_CTLT), a program chain sub-picture stream control table(PGC_SPST_CTLT), program chain navigation control information(PGC_NV_CTL), a program chain sub-picture palette (PGC_SP_PLT), thestart address (PGC_CMDT_SA) of a program chain command table, the startaddress (PGC_PGMAP_SA) of a program chain program map, the start address(C_PBIT_SA) of a playback information table of cells in the programchain, and the start address (C_POSIT_SA) of a position informationtable of cells in the program chain.

[0242] Program chain contents PGC CNT indicate the number of programsand number of cells (a maximum of 255) in the program chain. In aprogram chain having no video object VOB, the number of programs is “0”.

[0243] The program chain playback time (PGC_PB_TM) represents the totalplayback time of programs in that program chain in hours, minutes,seconds, and the number of video frames. This PGC_PB_TM also describes aflag (tc_flag) indicating the type of video frame, and a frame rate (25or 30 frames per sec) or the like is designated by the contents of thisflag.

[0244] Program chain user operation control information PGC_UOP_CTLindicates user operations prohibited in the program chain which is beingplayed back.

[0245] Program chain audio stream control table PGC_AST_CTLT can containcontrol information for each of eight audio streams. Each controlinformation includes a flag (availability flag) indicating if thecorresponding audio stream is available in that program chain, andconversion information from an audio stream number to an audio streamnumber to be decoded.

[0246] Program chain sub-picture stream control table PGC_SPST_CTLTincludes a flag (availability flag) indicating if that sub-picturestream is available in the corresponding program chain, and conversioninformation from a sub-picture stream number (32 numbers) into thesub-picture stream number to be decoded.

[0247] Program chain navigation control information PGC_NV_CTL includesNext-PGCN indicating the next program chain number to be played backafter the program chain which is currently being played back,Previous_PGCN indicating a program chain number (PGCN) quoted by anavigation command “LinkPrevPGC” or “PrevPGC_Search( )”, GoUp_PGCNindicating a program chain number to which that program chain is toreturn, a PG Playback mode indicating the playback mode (sequentialplayback, random playback, shuffle playback, and the like) of theprogram, and a Still time value indicating the still time after thatprogram chain is played back.

[0248] Program chain sub-picture palette PGC_SP_PLT describes 16 sets ofluminance signals and two color difference signals used in a sub-picturestream in that program chain.

[0249] Start address PGC_CMDT_SA of the program chain command tableassures a description area for a pre-command executed before PGCplayback, a post-command executed after PGC playback, and a cell commandexecuted after cell playback.

[0250] Start address PGC_PGMAP_SA of the program chain program mapdescribes the start address of program map PGC_PGMAP representing theprogram configuration in the program chain by a relative address fromthe first byte of program chain information PGCI.

[0251] Start address C_PBIT_SA of the cell playback information table inthe program chain describes the start address of cell playbackinformation table C_PBIT that determines the playback order of cells inthat program chain by a relative address from the first byte of programchain information PGCI.

[0252] Start address C_POSIT_SA of the position information table ofcells in the program chain describes the start address of cell positioninformation table C_POSIT indicating VOB identification numbers and cellidentification numbers used in that program chain by a relative addressfrom the first byte of program chain information PGCI.

[0253]FIG. 19 shows an example of the arrangement of an apparatus (DVDvideo recorder) for recording and playing back digital moving pictureinformation on and from a disc shown in FIG. 1 at a variable recordingrate using information with the structure described above with referenceto FIGS. 3 to 18.

[0254] The apparatus main body of the DVD video recorder shown in FIG.19 is roughly constructed by a disc drive unit (32, 34, and the like)for rotating DVD-RAM or DVD-R disc 10, and reading/writing informationto/from disc 10, encoder 50 on the recording side, decoder 60 on theplayback side, and microcomputer block 30 for controlling operations ofthe apparatus main body.

[0255] Encoder 50 comprises ADC (analog-to-digital converter) 52, videoencoder (V encoder) 53, audio encoder (A encoder) 54, sub-pictureencoder (SP encoder) 55, formatter 56, and buffer memory 57.

[0256] ADC 52 receives an external analog video signal+external analogaudio signal from AV input 42, or an a analog TV signal+analog audiosignal from TV tuner 44. ADC 52 converts the input analog video signalinto a digital signal at sampling frequencies of, e.g., 13.5 MHz/6.75 Mand 8 quantization bits. (That is, luminance component Y at a samplingfrequency of 13.5 M, color difference component Cr (or Y−R) at asampling frequency of 6.75 M, and color difference component Cb (or Y−B)at a sampling frequency of 6.75 M are respectively quantized, with theratio of 4:2:2, by 8 bits). Incidentally, all components Y, Cr and Cbmay be sampled with 13.5 M, so that they are quantized, in the ratio of4:4:4, by 8 bits.

[0257] Similarly, ADC 52 converts the input analog audio signal into adigital signal at a sampling frequency of, e.g., 48 kHz and 16quantization bits.

[0258] When an analog video signal and digital audio signal are input toADC 52, the digital audio signal passes through ADC 52. (The digitalaudio signal may be subjected to processing for reducing jitter alone,processing for changing the sampling rate or the number of quantizationbits, and the like without changing its contents.)

[0259] On the other hand, when a digital video signal and digital audiosignal are input to ADC 52, these signals pass through ADC 52 (thesesignals may also be subjected to jitter reduction, sampling rate changeprocessing, and the like without changing their contents).

[0260] A digital video signal component output from ADC 52 is suppliedto formatter 56 via video encoder (V encoder) 53. Also, a digital audiosignal component output from ADC 52 is supplied to formatter 56 viaaudio encoder (A encoder) 54.

[0261] V encoder 53 has a function of converting the input digital videosignal into a digital signal compressed at a variable bit rate by MPEG2or MPEG1.

[0262] A encoder 54 has a function of converting the input digital audiosignal into a digital signal compressed at a fixed bit rate (or linearPCM digital signal) by MPEG or AC-3.

[0263] When a DVD video signal with the data structure shown in FIGS. 11and 12 is input from AV input 42 (e.g., a signal coming from a DVD videoplayer with a dedicated sub-picture signal output terminal), or when aDVD video signal with such data structure is broadcasted and received byTV tuner 44, a sub-picture signal component (sub-picture pack) in theDVD video signal is input to sub-picture encoder (SP encoder) 55.Sub-picture data input to SP encoder 55 is arranged into a predeterminedsignal format, and is then supplied to formatter 56.

[0264] Formatter 56 performs predetermined signal processing for theinput video signal, audio signal, sub-picture signal, and the like whileusing buffer memory 57 as a work area, and outputs recording data thatmatches the format (file structure) described above with reference toFIGS. 3 to 18 to data processor 36.

[0265] The contents of standard encoding for generating the recordingdata will be briefly explained. That is, when encoder 50 shown in FIG.19 starts encoding, parameters required for encoding video (mainpicture) data and audio data are set. The main picture data ispre-encoded using the set parameters to calculate an optimal code amountdistribution for a predetermined average transfer rate (recording rate).Based on the code amount distribution obtained by pre-encoding, the mainpicture data is encoded. At this time, the audio data is encoded at thesame time.

[0266] As a result of pre-encoding, when data compression isinsufficient (when a desired video program cannot be stored in a DVD-RAMor DVD-R disc used to record data), if pre-encoding can be done again(for example, if the recording source is the one capable of repetitiveplayback such as a video tape, video disc, or the like), the mainpicture data is partially re-encoded, and the re-encoded main picturedata portion replaces the previously pre-encoded main picture dataportion. With a series of such processes, the main picture data andaudio data are encoded, and the average bit rate value required forrecording is reduced largely.

[0267] Likewise, parameters required for encoding the sub-picture dataare set, and encoded sub-picture data is generated.

[0268] The encoded main picture data, audio data, and sub-picture dataare combined and converted into the structure of video title set VTS.

[0269] That is, cells as minimum units of the main picture data (videodata) are set, and the cell playback information (C_PBI) is generated.Then, the structure of cells that construct a program chain shown inFIG. 8, attributes of main picture, sub-picture, and audio data, and thelike are set (some of these attributes use information obtained uponencoding the individual data), and information management tableinformation (VMGI_MAT in FIG. 15 and VTSI_MAT in FIG. 16) containingvarious kinds of information is created.

[0270] The encoded main picture data, audio data, and sub-picture dataare segmented into packs each having a predetermined size (2,048 bytes)shown in FIG. 12, and dummy packs are appropriately inserted into thesepacks. Packs other than the dummy packs describe time stamps such as aPTS (presentation time stamp), DTS (decode time stamp), and the like. Asfor the PTS of sub-picture data, a time arbitrarily delayed from that ofmain picture data or audio data in the same playback time zone can bedescribed.

[0271] The data cells are arranged while adding navigation pack 86 atthe beginning of each VOBU 85 so as to play back data in the order fromtheir time codes, thus forming VOB 83 constructed by a plurality ofcells, as shown in FIG. 11. VOBS 82 containing one or more VOBs 83 isformatted to the structure of VTS 72 shown in FIG. 8.

[0272] When a DVD playback signal is digitally copied from a DVD videoplayer, since the contents of cells, program chain, management tables,time stamps, and the like are predetermined, they need not be generatedagain. (When a DVD video recorder is designed to digitally copy a DVDplayback signal, copyright protection means such as an electronicwatermark, and the like must be taken.)

[0273] The disc drive unit that writes/reads (records/plays back)information to/from DVD disc 10 comprises disc changer 100, disc drive32, temporal storage 34, data processor 36, and system time counter (orsystem time clock; STC) 38.

[0274] Temporal storage 34 is used for buffering a predetermined amountof those of data to be written in disc 10 via disc drive 32 (i.e., dataoutput from encoder 50), and for buffering a predetermined amount ofthose of data played back from disc 10 via disc drive 32 (i.e., datainput to decoder 60).

[0275] For example, when temporal storage 34 is comprised of a 4 Mbytesemiconductor memory (DRAM), it can buffer recording or playback datafor approximately 8 sec at an average recording rate of 4 Mbps. On theother hand, when temporal storage 34 is comprised of a 16 Mbyte EEPROM(flash memory), it can buffer recording or playback data forapproximately 30 sec at an average recording rate of 4 Mbps.Furthermore, when temporal storage 34 is comprised of a 100 Mbyte verycompact HDD (hard disc), it can buffer recording or playback data for 3min or more at an average recording rate of 4 Mbps.

[0276] Temporal storage 34 can also be used for temporarily storingrecording information until disc 10 is exchanged by a new one, when disc10 has been fully recorded during recording.

[0277] Temporal storage 34 can be used for temporarily storing dataexcessively read out from the drive within a predetermined period oftime when disc drive 32 uses a high-speed drive (double-speed orhigher). When read data upon playback is buffered on temporal storage34, even when an optical pickup (not shown) has produced read errors dueto a vibration shock or the like, playback data buffered on temporalstorage 34 can be used alternatively, thus preventing a played backpicture from being interrupted.

[0278] When the DVD video recorder has an external card slot (not shownin FIG. 19), the EEPROM may be sold as an optical IC card. On the otherhand, when the DVD video recorder has an external drive slot or SCSIinterface, the HDD can be sold as an optical expansion drive.

[0279] Data processor 36 in FIG. 19 supplies DVD recording data outputfrom encoder 50 to disc drive 32, receives a DVD playback signal playedback from disc 10 via drive 32, rewrites management information (thedirectory records described subsequent to FIG. 10, VMGI_MAT in FIG. 15,VTSI_MAT in FIG. 16, and the like) recorded in disc 10, and erases data(files or VTS) recorded on disc 10 under the control of microcomputerblock 30.

[0280] Microcomputer block 30 includes an MPU (or CPU), a ROM writtenwith control programs and the like, and a RAM that provides a work arearequired for executing programs.

[0281] The MPU in microcomputer block 30 (to be also referred to as MPU30 hereinafter) executes free space detection, recording amount (thenumber of recorded packs) detection, remaining amount detection,warning, recording mode change instruction, and other processes usingthe RAM as a work area in accordance with the control programs stored inthe ROM.

[0282] Of the execution results of MPU 30, the contents that the DVDvideo recorder user is informed of are displayed on display 48 of theDVD video recorder, or are displayed on a monitor display in anon-screen display (OSD) mode.

[0283] The control timings of disc changer 100, disc drive 32, dataprocessor 36, and encoder 50 and/or decoder 60 by MPU 30 can bedetermined based on time data output from STC 38 (recording and playbackare normally done in synchronism with time clocks from STC 38, but otherprocesses may be executed at timings independently of STC 38).

[0284] Decoder 60 comprises separator 62 for separating and extractingpacks from DVD playback data with the pack structure shown in FIG. 11,memory 63 used upon signal processes such as pack separation and thelike, video decoder (V decoder) 64 for decoding main picture data (thecontents of video pack 88 in FIG. 11) separated by separator 62,sub-picture data decoder (SP decoder) 65 for decoding sub-picture data(the contents of sub-picture pack 90 shown in FIG. 11) separated byseparator 62, audio decoder (A decoder) 68 for decoding audio data (thecontents of audio pack 91 in FIG. 11) separated by separator 62, videoprocessor 66 for appropriately synthesizing sub-picture data output fromSP decoder 65 with video data output from V decoder 64, and outputtingmain picture data with superimposed sub-picture data such as menus,highlight buttons, superimposed dialog, and the like, videodigital-to-analog converter (V.DAC) 67 for converting a digital videooutput from video processor 66 into an analog video signal, and audiodigital-to-analog converter (A.DAC) 67 for converting a digital audiooutput from A decoder 68 into an analog audio signal.

[0285] The analog video signal output from V.DAC 67 and analog audiosignal from A.DAC 69 are supplied to output device 46 a (not shown; amultichannel stereophonic apparatus having two to six channels+ monitorTV or projector) via AV output 46.

[0286] OSD data output from MPU 30 is input to separator 62 of decoder60, and is then input to video processor 66 through V decoder 64(without being decoded). The OSD data is superimposed on main picturedata, and these data are supplied to an external monitor TV connected toAV output 46. Then, a warning message is displayed together with a mainpicture.

[0287] MPU 30 is connected to printer interface P1. Printer interface P1is connected to printer P2. Printer P2 prints out images based onvarious data played back from optical disc 10 to predetermined locations(an optical disc, a label added to an optical disc, a cartridge whichstores an optical disc, and the like).

[0288] When the user has pressed open/close button 5 g of remotecontroller (to be described later with reference to FIG. 20), a disctray (not shown) is opened toward the user side.

[0289] DVD-RAM or DVD-RW disc (a cartridge containing a disc) 10 orDVD-R disc (bear disc) 10 used in recording is set on this disc tray.

[0290] Subsequently, when the user has pressed open/close button 5 g onremote controller 5, disc tray door 202 is closed, and disc (e.g.,DVD-RW) set on the tray is loaded into disc drive 32 in apparatus mainbody 200.

[0291] Then, disc drive 32 is automatically started, and MPU 30 readsphysical format information (including disc structure data, free spacedata of a blank disc, and the like). After that, MPU 30 reads a videomanager information management table (including information FREE_SPACEindicating a practical free space, and the like) shown in FIG. 15, and avideo title set information management table (including PLAY_END Flagindicating whether or not a specific title set has already been playedback, ARCHIVE Flag indicating whether or not a specific title set is tobe permanently kept, and the like) shown in FIG. 17.

[0292] When set disc 10 is a new DVD-RW disc (or DVD-RAM disc), an item“DVD-RW” (or “DVD-RAM”) on display 48 of the DVD video recorder is beingprominented in an easy-to-see manner. Also, a recording time “00 (hour):00 (min): 00 (sec)” is displayed, and a recording title/chapter “00-00”is displayed (once recording has been done, the recording title/chapterdisplay changes like “01-01”).

[0293] If the apparatus default or user setup indicates a recordingmode=MPEG2 and a recording average bit rate=4 Mbps, items “MPEG2” and “4Mbps” are displayed on display 48 to stand out.

[0294] Furthermore, when recording on set disc 10 has progressed, andthe recordable time on that disc 10 becomes small (e.g., 5 min), MPU 30detects it, and an item “DISK TO BE CHANGED” that prompts the user toexchange the disc is displayed on display 48 in an easy-to-see manner.

[0295] The front panel of DVD video recorder main body 200 also hasbasic operation keys such as a power switch button, open/close key,playback key, stop key, chapter/program skip key, rewind key,fastforward key, recording start button (not shown), and the like.

[0296] The above-mentioned item “DISK TO BE CHANGED” begins to be lit upor flicker slightly before disc 10 set in the apparatus main body isused up during recording. After that when the remaining amount of disc10 becomes zero, recording automatically proceeds to one or more DVD-RWdisc 10 set in external disc changer 100.

[0297] Alternatively, two or more DVD video recorders may be prepared,and their MPUs 30 may be connected by daisy chain via a communicationcable to attain relay recording using two or more DVD video recorders.In such case, it is possible that “the first recorder can record usingMPEG2/average bit rate=4 Mbps for 1 hour, and the second recorder canrecord using MPEG2/average bit rate=2 Mbps for 2 hours”.

[0298] In case of relay recording using a plurality of DVD videorecorders, a message “recorder A records using MPEG2/average bit rate=4Mbps for 1 hour, and recorder B records using MPEG2/average bit rate=2Mbps for 2 hours” may be displayed on the monitor screen.

[0299] Note that the DVD video recorder shown in FIG. 19 does not recordany warning or messages to the user on disc 10. However, recordinginformation (recording average bit rate, recording channel number,recording date/time, and the like) exemplified on the lower portion ofthe monitor screen may be recorded on disc 10 for several secondsimmediately after the beginning of recording.

[0300]FIG. 20 shows an example of remote controller 5 used for operatingthe DVD video recorder shown in FIG. 19. Remote controller 5 shown inFIG. 20 has various keys such as power key 5 a, open/close key 5 g, menukey 5 n, select/cursor key 5 q, display key 5 u, and print key 5 pri.

[0301] Power key 5 a is literally used to turn on/off the power supply.Open/close key 5 g is used to open/close disc tray 202 (not shown)mounted on apparatus main body 200 of the DVD video recording shown inFIG. 19. Menu key 5 n is used to play back/display root menus recordedon a disc and selected menus. Select/cursor key 5 q is used to selectvarious items. Display key 5 u is used to display various pieces ofinformation on display 48. The function of print key 5 pri will beexplained in detail below.

[0302] A representative frame will be described.

[0303] Video object DA22 of optical disc 10 includes moving picture dataconstructing a plurality of chapters (first, second, . . . , nthchapters). This moving picture data includes a plurality of picture datacorresponding to a plurality of frames. The plurality of frames includerepresentative frames each representing a corresponding chapter. Therepresentative frame is a frame to be reduced for the following reason.The representative frame is also a frame to be printed. Picture datacorresponding to this representative frame is the above-describedrepresentative picture data. That is, information indicating the storagelocation of the representative picture data is start address data INFO11and length data INFO12.

[0304] The relationship between a main frame and subframe will beexplained.

[0305] Moving picture data included in video object DA22 of optical disc10 is data compressed by a compression format determined by MPEG2. Thismoving picture data includes base picture data corresponding to a basepicture (I picture: Intra-Picture), and change data indicating a change(motion) in base picture. The base picture data included in the movingpicture data forms a main frame, and the change data forms a subframe.The subframe is a picture subsequent to the main frame. That is, mainpicture data (base picture data) corresponding to the main frame, andsub-picture data corresponding to the subframe are played back in thisorder. In this embodiment, for example, the representative framecorresponds to the main frame. In other words, information indicatingthe storage location of main picture data corresponding to the mainframe is start address data INFO11 and length data INFO12.

[0306] The skip playback function will be explained.

[0307] The digital information recording/playback system has a function(skip playback function) of playing back moving picture data from apredetermined position (predetermined chapter). To realize this skipplayback function, picture object DA23 of optical disc 10 records menuframe information for creating a skip playback menu frame. When thedigital information recording/playback system receives a menu displayinstruction via menu key 5 n of remote controller 5, it reads menu frameinformation from optical disc 10 and displays a skip playback menu frameon output device (monitor or the like) 46 a based on this menu frameinformation.

[0308] The skip playback menu frame includes the first representativeframe representing the first chapter, the second representative framerepresenting the second chapter, . . . , and the nth representativeframe representing the nth chapter. In displaying the skip playback menuframe, the digital information recording/playback system reads startaddress data INFO11 and length data INFO12 and reads out representativepicture data from the storage location of the representative picturedata. This representative picture data is reduced to display arepresentative frame of each chapter on the skip playback menu frame. Atthis time, if the digital information recording/playback system receivesdesignation of a predetermined representative frame via selectkey/cursor key 5 q of remote controller 5, it starts playing back movingpicture data from a chapter corresponding to the predeterminedrepresentative frame. In this way, the skip playback function isrealized.

[0309] Printing of information about the recording contents of opticaldisc 10 will be described.

[0310] According to the present invention, information about therecording contents of optical disc 10 is printed on the surface ofoptical disc 101 a cartridge which stores optical disc 10, or a labeladded to optical disc 10. This allows the user to obtain informationabout the recording contents of optical disc 10 without playing backoptical disc 10. Information about the recording contents of opticaldisc 10 corresponds to representative picture data equivalent to arepresentative frame (a frame to be printed or main frame). Informationabout the recording contents of optical disc 10 also includes pictureinformation INFO7 (recording date information INFO71, recording channelinformation INFO72, white balance information INFO73, zoom ratioinformation INFO74, shutter speed information INFO75, and GPSinformation INFO76). Further, information about the recording contentsof optical disc 10 also includes amount information 271 (total amountinformation 2711 and free area information 2712), and rewrite countinformation 701.

[0311] Printing of information about the recording contents of opticaldisc 10 will be explained with reference to a flow chart in FIG. 21.

[0312] The digital information recording/playback system has a function(recording-related matter printing function) of printing informationabout the recording contents of optical disc 10. To realize thisrecording-related matter printing function, volume/file managementinformation 70 of optical disc 10 records menu frame information forcreating a print menu frame. When the digital informationrecording/playback system receives a recording-related matter printinstruction via print key 5pri of remote controller 5 (YES in ST1), itreads menu frame information from optical disc 10 and displays a printmenu frame on output device 46 a based on this menu frame information(ST2).

[0313] Print targets are displayed on the print menu frame. That is,representative frames (first, second, . . . , nth representativeframes), picture information INFO7 (recording date information INFO71,recording channel information INFO72, white balance information INFO73,zoom ratio information INFO74, shutter speed information INFO75, and GPSinformation INFO76), amount information 271 (total amount information2711 and free area information 2712), rewrite count information 701, andthe like are displayed on the print menu frame. In displaying the printmenu frame, the digital information recording/playback system readsstart address data INFO11 and length data INFO12 and reads outrepresentative picture data form the storage location of therepresentative picture data. This representative picture data is reducedto display a representative frame of each chapter on the print menuframe. In displaying the print menu frame, the digital informationrecording/playback system reads picture information INFO7 (recordingdate information INFO71, recording channel information INFO72, whitebalance information INFO73, zoom ratio information INFO74, shutter speedinformation INFO75, and GPS information INFO76), amount information 271(total amount information 2711 and free area information 2712), andrewrite count information 701. The digital informationrecording/playback system displays the read information on the printmenu frame.

[0314] If the digital information recording/playback system receivesdesignation of a print target via the operation panel after the printmenu frame is displayed on output device 46 a (YES in ST3), it instructsthe printer to print the designated print target. The printer executesimage formation based on data of the designated print target inaccordance with this instruction. That is, the printer prints thedesignated print target to a predetermined print destination (ST4). Theprint destination at this time is the surface of optical disc 10, acartridge which stores optical disc 10, a label added to optical disc10, or the like.

[0315]FIG. 22 is a view showing the state in which picture informationINFO7 (recording date information INFO71, recording channel informationINFO72, white balance information INFO73, zoom ratio information INFO74,shutter speed information INFO75, and GPS information INFO76) is printedon a label added to optical disc 10 and cartridge 11.

[0316]FIGS. 23A, 23B, and 23C are views showing the state in whichamount information 271 (total amount information 2711 and free areainformation 2712) is printed on a label added to cartridge 11. FIG. 23Ais a view showing the state in which amount information 271 (free area)is numerically represented. FIG. 23B is a view showing the state inwhich amount information 271 (remaining recording time) is numericallyrepresented. The recording time changes in accordance with thecompression ratio of image data recorded on optical disc 10, so anaccurate remaining recording time cannot be obtained from a free area.In this case, an approximate remaining recording time is printed. FIG.23C is a view showing the state in which amount information 271 (freearea) is illustrated. By representing used and unused amounts incontrast with each other, as shown in FIG. 23C, the user can visuallycheck the storage amount.

[0317]FIGS. 24A and 24B are views showing the state in which rewritecount information 701 is printed on a label added to optical disc 10.Data is assumed to be frequently rewritten on an optical disc such asDVD-RAM. However, the number of rewrite operations is limited, and ifthe rewrite count exceeds a given count, a write disable area isgenerated. The write disable area is replaced, but too many writedisable areas result in a short of the data recording time owing toreplacement and data recording errors. To make the user know this inadvance, the rewrite count is printed. FIG. 24A is a view showing thestate in which rewrite count information 701 is numerically represented.FIG. 24B is a view showing the state in which rewrite count information701 is illustrated.

[0318] According to the present invention, an information recordingmedium processing apparatus which can easily display information aboutthe recording contents of an information recording medium without anyplayback and cumbersome processing of the information recording medium(optical disc) can be provided.

[0319] According to the present invention, an information recordingmedium which can contribute to easy display of information about therecording contents of the information recording medium without anyplayback and cumbersome processing of the information recording medium(DVD-RAM disc).

[0320] A modification of the embodiment mentioned above will bedescribed with reference to FIGS. 25 to 31. In the above embodiment,start address data INFO11 and length data INFO12 shown in FIG. 7indicate the storage location of a representative picture included invideo object DA22 shown in FIG. 3. However, the present invention is notlimited to this, and the storage go location of the representativepicture may be indicated as follows.

[0321] <1> General Description of Data Structure of InformationRecording Medium (Optical Disk 1001)

[0322] Data (video data, audio data, and the like) recorded on opticaldisc 1001 shown in the uppermost stage in FIG. 25 has a structure shownin the second stage in FIG. 25 from inner side 1006 to outer side 1007.The data structure shown in the second stage in FIG. 25 has detailsshown in the third, fourth, fifth, and sixth stages in FIG. 25.

[0323] More specifically, as shown in FIG. 25, optical disc 1001includes lead-in area 1002, volume & file manager information 1003, dataarea 1004, and lead-out area 1005. Lead-in area 1002 includes anembossed data zone having an uneven optical reflection surface, a mirrorzone having a flat surface (mirror surface), and a rewritable data zonecapable of information rewrite. Volume & file manager information 1003includes a rewritable data zone capable of recording/rewriting an audio& video data file or information about the total volume by the user.Data area 1004 includes a rewritable data zone capable ofrecording/rewriting data by the user. Lead-out area 1005 includes arewritable data zone capable of information rewrite.

[0324] The embossed data zone of lead-in area 1002 records in advanceinformation about the whole disc, information about recording, playback,and erase characteristics, and information about the manufacture of thedisc. Information about the whole disc is information such as the disctype (DVD-ROM, DVD-RAM, DVD-R, or the like), the disc size, therecording density, the physical sector number (PSN) indicating therecording start/end position, and the like. Information about recording,playback, and erase characteristics is information such as the recordingpower, the recording pulse width, the erase power, the playback power,the recording/erase linear velocity, and the like. Information about themanufacture of the disc is information about the manufacture of eachdisc such as the manufacturing number.

[0325] The rewritable data zones of lead-in and lead-out areas 1002 and1005 have unique disc name recording areas for respective informationrecording media, test recording areas (for confirming recording/eraseconditions), and management information recording areas about defectiveareas in data area 1004. These areas allow recording by the informationrecording/playback system.

[0326] As shown in FIG. 25, data area 1004 sandwiched between lead-inand lead-out areas 1002 and 1005 allows mixed recording of computer dataand audio & video data. The recording order and recording informationsizes of computer data and audio & video data can be arbitrarily set.Areas which record computer data will be called computer data areas 1008and 1010, and an area which records audio & video data will be calledaudio & video data area 1009.

[0327] As shown in FIG. 25, audio & video data area 1009 includescontrol information 1011, video objects 1012, picture objects 1013, andaudio objects 1014. Control information 1011 is control informationnecessary for processes such as picture recording (sound recording),playback, editing, and search. Video objects 1012 are contents(recording information) of video data. Picture objects 1013 are stillpicture information such as still pictures and slide pictures. Audioobjects 1014 are contents (sound recording information) of audio data.

[0328] Video objects 1012, picture objects 1013, and audio objects 1014shown in FIG. 25 mean information groups classified in units of contents(data contents). All video data recorded in audio & video data area 1009are included in video objects 1012, all pieces of still pictureinformation are included in picture objects 1013, and all audio-sounddata are included in audio objects 1014.

[0329] Original cell=VOB (video object) 1403 shown in FIG. 27 representsa set of pieces of information recorded in AV file 1401, and has adefinition different from that of video objects 1012 shown in FIG. 25.These terms are similar but used with different meanings.

[0330] As shown in FIG. 25, control information 1011 includes RTRW videomanager information (RTRW_VMGI) 1021, movie AV file information table(M_AVFIT) 1022, still picture AV file information table (S_AVFIT) 1023,original PGC information (ORG_PGCI) 1024, user defined PGC informationtable (ORG_PGCI) 1025, text data manager (TXT_DT_MG) 1026, andmanufactures information table (MNFIT) 1027. RTRW video managerinformation (RTRW_VMGI) 1021 is common to all RTR (Real Time Recording)shown in FIG. 26, and includes information indicating the storagedestination of a representative picture. The representative picture isused as a picture to be printed on a disc label (a picture representingthe recording contents of a disc). Alternatively, when a plurality ofdiscs are handled in an autochanger or multi-disc pack, therepresentative picture is used as a picture representing the recordingcontents of a disc loaded into the disc drive (a picture displayed as apreview on the display). Movie AV file information table (M_AVFIT) 1022and still picture AV file information table (S_AVFIT) 1023 manage datastructures in video object 1012, and information about recordingpositions on optical disc 1001. Original PGC information (ORG_PGCI) 1024and user defined PGC information table (ORG_PGCI) 1025 have controlinformation necessary for playback. Text data manager (TXT_DT_MG) 1026and manufactures information table (MNFIT) 1027 correspond to additionalrecording/playback information.

[0331] As shown in FIG. 25, movie AV file information table (M_AVFIT)1022 and still picture AV file information table (S_AVFIT) 1023 includeallocation map table 1105, video title set information 1106, and videoobject information 1107. Original PGC information (ORG_PGCI) 1024 anduser defined PGC information table (ORG_PGCI) 1025 include PGC controlinformation 1103 and cell playback information 1108. Allocation maptable 1105 records information about address setting along practicalallocation on optical disc 1001 and identification of recorded andunrecorded areas. Video title set information 1106 represents theoverall information in AV file 1401 shown in FIG. 27, and includes linkinformation between VOBs, grouping information of a plurality of VOBsfor management and search, and time information such as a time maptable. As shown in FIG. 27, video object information 1107 representsinformation about each VOB in AV file 1401, and includes attribute(characteristic) information for each VOB and information about eachvideo object unit (VOBU) contained in the VOB. PGC control information1103 includes information about a video data playback program(sequence). Cell playback information 1108 includes information aboutthe data structure of a basic video data unit for playback.

[0332] The structure in FIG. 25 has been schematically explained, andeach information will be slightly supplementally explained.

[0333] Volume & file manager information 1003 records information aboutthe total volume, the number of PC data files, the number of AV datafiles, and recording layer information.

[0334] In particular, as the recording layer information, the followinginformation is recorded to process a multi-disc pack or two-layeredRAM/ROM disc as one large volume space by setting successive logicalsector numbers.

[0335] The number of constituent layers (e.g., one two-layered RAM/ROMdisc is counted as two layers, one two-layered ROM disc is counted astwo layers, and n single-sided discs are counted as n layers.)

[0336] A logical sector number range table assigned to each layer (theamount of each layer)

[0337] The type of each layer (e.g., a DVD-RAM disc, a RAM portion of atwo-layered RAM/ROM disc, a CD-ROM, a CD-R, or the like)

[0338] A logical sector number range table assigned in units of zones inthe RAM area of each layer (also including rewritable area amountinformation of each layer)

[0339] ID information unique to each layer (to check disc exchange in amulti-disc pack)

[0340] <2> Directory Structure of Data File in Data Area 1004

[0341] All pieces of information recorded in data area 1004 in FIG. 25are recorded in units of files, and the relationship between data filesis managed by a directory structure, as shown in FIG. 26.

[0342]FIG. 39 illustrates the directory and files where the data whichcomplies with this Specifications are recorded. All the files associatedwith the Program Set and Play Lists are Placed under DVD_RTR directory.Under the directory, the following files are created.

[0343] RTR.IFO

[0344] Navigation data to represent Programs Entry Points, Play Lists,and so on are recorded in this file. This file shall exists as long asany contents compliant to this Specifications are recorded. TheNavigation data to be recorded in this file are to be described in thefollowing sections.

[0345] RTR_MOV.VRO

[0346] Stream data categorized in Movie VOB are recorded in this file.Therefore as long as any Movie VOB exists, this file shall exist.

[0347] Control information 1011 in FIG. 25 is recorded as one fileserving as recording/playback video management data. Control information1011 in FIG. 25 has a file name “RTR.IFO” in FIG. 26. Video objects 1012in FIG. 25 have a file name “RTR_MOV.VRO” in FIG. 26. Picture objects1013 in FIG. 25 have a file name “RTR_STO.VRO” in FIG. 26. Audio objectsin FIG. 25 have a file name “RTR_STA.VRO” in FIG. 26. RTRW_STA.VROrepresents an after-recording file of a still picture (RTRW_STO.VRO).Video objects 1012, picture objects 1013, and audio objects 1014 arerecorded as one AV file 1401 shown in FIG. 27.

[0348] <3> Data Structure in AV File

[0349]FIG. 27 shows a data structure in the AV file. As shown in FIG.27, AV file 1401 constitutes program set (original PGC) 1402 as a whole.Program set 1402 consists of a set of a plurality of original cells=VOBs(video objects) 1403, 1404, and 1405 divided in accordance with thecontents of audio & video data and the order of information recorded inAV file 1401.

[0350] VOBs 1403, 1404, and 1405 in FIG. 27 are defined as a set ofaudio & video data recorded in AV file 1401, and have definitioncontents different from those of video objects 1012 shown in FIG. 25that substantially serve as classification items for video data, stillpicture information, audio data, and the like. Therefore, VOBs 1403,1404, and 1405 in FIG. 27 record not only information classified intovideo objects 1012, but also information classified into picture objects1013 and audio objects 1014.

[0351] Contents recorded in VOBs 1403, 1404, and 1405 are grouped inunits of related VOBs, and respective groups are combined as PGs(programs) 1407 and 1408. That is, PGs 1407 and 1408 are constituted assets of one or plurality of VOBs. In FIG. 27, PG 1408 is constituted bytwo VOBs 1404 and 1405, and PG 1407 is constituted by only one VOB.

[0352] The minimum basic units of video data are called VOBU 1411 to1414, and data in VOBs 1403 to 1405 are constituted as sets of VOBUs(video object units) 1411 to 1414, as shown in FIG. 27. Video datacompression using the VOB often employs MPEG1 or MPEG2. In MPEG, videodata are grouped into GOPs every 0.5 sec, and compressed in units ofGOPs. The video data compression unit of VOBUs 1411 to 1414 is formed insynchronism with the GOP with almost the same size as that of the GOP.

[0353] VOBUs 1411 to 1414 include one or more frames. More specifically,VOBUs 1411 to 1414 are divisionally recorded as 2,048 byte sectors 1431to 1437. Each of sectors 1431 to 1437 is recorded with a pack structureformat. In units of packs, raw video data, sub-video data, audio data,and dummy data are recorded in the forms of V_PCKs (Video Packs) 1421,1425, 1426, and 1427, SP_PCK (Sub-picture Pack) 1422, A_PCK (Audio Pack)1423, DM_PCK (Dummy Pack) 1424. Each pack has a 14 byte pack header atits beginning, and thus the information amount recorded in each pack is2,034 bytes.

[0354] The recording area of a DVD-RAM disc as an example of opticaldisc 1001 shown in FIG. 25 is divided into a plurality of sectors. Onesector can record 2,048 byte data. On this DVD-RAM disc,recording/playback is performed in units of sectors. When the DVD-RAMdisc is used as optical disc 1001, respective packs are recorded inunits of sectors 1431 to 1437, as shown in FIG. 27.

[0355] As shown in FIG. 27, a series of all VOBs 1403 to 1405 in AV file1401 constitute program set 1402. An arbitrary range in an arbitrary VOBis designated and played back in an arbitrary playback order inaccordance with a playback procedure programmed in original PGCinformation (ORG_PGCI) 1024 and user defined PGC information table(ORG_PGCI) 1025. The basic video data basic unit for playback will becalled cells (user defined cells) 1441, 1442, and 1443. Cells 1441,1442, and 1443 can designate an arbitrary range in an arbitrary VOB, butcannot designate a range over VOBs (one cell cannot set a range bylinking a plurality of VOBs).

[0356] In FIG. 27, cell 1441 designates one VOBU 1412 in VOB 1403, cell1442 designates one entire VOB 1404, and cell 1443 designates the rangeof only a specific pack (V_PCK 1427) in VOBU 1414.

[0357] Information representing the video data playback sequence is setby PGC (user defined program chain) 1446. This playback sequence isdesignated by one cell or described by link information between aplurality of cells. For example, in FIG. 27, PGC 1446 constitutes aplayback program as a link between cells 1441, 1442, and 1443.

[0358] <4> Contents of Allocation Map Table

[0359] As described above, the recording area of the DVD-RAM disc isdivided into a plurality of sectors, and the sectors are added withlogical sector numbers (LSNs) in an ascending order from the inner side.

[0360] Assume that video data is recorded in data area 1004 of opticaldisc 1001 by the following procedure.

[0361] (1) A recording area of AV file 1401 is ensured in a continuousarea (a<g) from LSNs a+1 to g in data area 1004 on optical disc 1001.

[0362] (2) Data of VOB#1 1461 is recorded in a continuous area (b<c)from LSNs b+1 to c in the recording area of AV file 1401.

[0363] (3) Data of VOB#2 1462 is recorded in a continuous area (d<e)from LSNs d+1 to e in the recording area of AV file 1401.

[0364] As a result of processes (1) to (3), three unrecorded areas fromLSN “a+1 to b”, “c+1 to d”, and “e+1 to g” are left in AV file 1401.Video data of VOB#3 having a large data size is recorded in theunrecorded areas by the following procedure.

[0365] (4) Data of VOB#3 is divided into a plurality of segments inaccordance with the unrecorded area size in the recording area of AVfile 1401.

[0366] (5) The first data of the divided VOB#3 is recorded in acontinuous area (a<b) from LSN a+1 to b.

[0367] (6) The second data of the divided VOB#3 is recorded in acontinuous area (c<d) from LSN c+1 to d.

[0368] (7) The last data of the divided VOB#3 is recorded in acontinuous area (f<g) from LSN f+1 to g.

[0369] Consequently, unrecorded area 1460 from LSN “e+1 to f” is left inAV file 1401. FIG. 28 shows the physical recording position distributionof respective VOBs in AV file 1401 that is obtained as a result ofprocesses (1) to (7).

[0370] As is apparent from the above description, if data in AV file1401 is partially erased, or new data is repetitively recorded in anunrecorded area of AV file 1401, one VOB data must be distributivelyrecorded on a plurality of portions, like VOB#3 1463, 1464, and 1465.

[0371] Information representing the physical recording positiondistribution of respective data distributively recorded in units of VOBsin single AV file 1401 is allocation map table 1105 shown in FIG. 25.FIG. 29 As shows the information contents of allocation map table 1105for the data allocation in FIG. 28 used as an example. Allocation maptable 1105 consists of unrecorded area position distribution information1621, and data recording position distribution information 1622, 1623,and 1624 in units of VOBs.

[0372] A set in which a link between successive LSNs is assured in eachVOB is defined as “extent”. In FIG. 28, data of VOB#3 is separatelyrecorded as three sets. In this example, since LSNs a+1 to b are linkedas successive LSNS, this area constitutes “extent #γ 1473”. That is, theposition distribution where data of VOB#3 is recorded has tree extents#γ 1473, #δ 1474, and #ε 1475.

[0373] The number of extents 1601, 1602, 1603, and 1604 is recorded atthe beginning of the unrecorded area and position distributioninformation about each VOB in allocation map table 1105 shown in FIG.29. Subsequently, start addresses 1606, 1607, 1608, 1609, 1610, and 1611and extent sizes 1614, 1615, 1616, 1617, 1618, and 1619 are recorded.The start address is expressed by a “difference number” from the firstLSN in AV file 1401. By expressing the start address by the differencenumber, information in allocation map table 1105 need not be changedwhen the whole contents of AV file 1401 are transferred to anotheroptical disc, resulting in high file transferability. In addition, asshown in FIG. 29, the extent size is expressed by the number of sectors.Instead of expressing the extent size as shown in FIG. 29, the extentsize may be expressed by the final address of the extent.

[0374] In the DVD-RAM disc standard, a physical address on optical disc1001 is called a physical sector number (PSN), and all addresses used inthe file system are called logical sector numbers (LSNs), and an addressdefined on the file system in data area 1004 in FIG. 25 is called alogical block number (LBN). However, faithfully according to thisdescription, an explanation becomes complicated. For this reason, inFIGS. 28 and 29, the address is expressed by the logical sector numberfor the sake of simplicity.

[0375] The data structure of RTRW video manager information (RTRW_VMGI)1021 will be explained. RTRW video manager information (RTRW_VMGI) 1021has, e.g., a data structure shown in FIG. 30, 31, or 32.

[0376] The data structure shown in FIG. 30 will be first explained. Asshown in the upper stage in FIG. 30, RTRW video manager information(RTRW_VMGI) 1021 includes a video manager information management table(VMGI_MAT) and play list pointer table (PL_LPT). The video managerinformation management table (VMGI_MAT) includes a total of 512 bytedata shown in the middle stage in FIG. 30. This 512 byte data includesREP_PICTI. REP_PICTI includes data shown in the lower stage in FIG. 30.

[0377] Specific data in FIG. 30 will be explained briefly.

[0378] (RBP 149 to 163)REP_PICTI

[0379] Describes disc Representative Picture Information as follows.

[0380] Note: Setting and using this Disc Representative PictureInformation is an optional function for both Recorders and players.Recorders which don't have capability to handle this information may set‘FFH’ to all 15 bytes of REP_PICTT. Players which don't have capabilityto handle this information may simple ignore this information.

[0381] (RBP 149)PGCN

[0382] Describes the PGC number in which this Disc RepresentativePicture exists. The Disc Representative Picture is specified as pointerin the original PGC. So, when this picture pointer exists, set ‘0’ toPGCN.

[0383] (RBP 150)PGN

[0384] Describes the PG number in which this Disc Representative Pictureexists.

[0385] (RBP 151 to 152)CN

[0386] Describes the Cell number in which this Disc RepresentativePicture exists.

[0387] (RBP 153 to 158)PICT_PT

[0388] Describes the Disc Representative Picture in the target Cell.When this picture exists in a Movie Cell, PICT_PT describes thePresentation Time (PTM). When this picture exists in a Still PictureCell, PICT_PT describes the Still Picture VOB Entry number (S_VOB_ENTN)in the corresponding Still Picture VOB group (S_VOG) as follows.

[0389] The representative picture is extracted from these specific data.Instead, the VOB number may be used. The VOB number indicates a givenVOB (VOB number) in the disc.

[0390] The data structure shown in FIG. 31 will be explained. As shownin the upper stage in FIG. 31, RTRW video manager information(RTRW_VMGI) 1021 includes a video manager information management table(VMGI_MAT) and a play list pointer table (PL_LPT). As shown in themiddle stage in FIG. 31, the video manager information management table(VMGI_MAT) includes a 12 byte (0 to 11) VMG identifier (VMG_ID), a 4byte (12 to 15) end address of RTRWI (RTRWI_EA), a 4 byte (16 to 19)start address of representation picture VOBU (RPV_SA), a 1 byte (20 to20) frame number in representation picture VOBU (RIP_FN), a 7 byte (21to 27) reserved, a 4 byte (28 to 31) end address of VMGI (VMGI_EA), a 2byte (32 to 33) version number of DVD RTRW video specification (VERN),and a 2,014 byte (34 to 2,047) reserved. A target representation picture(a representation picture is first I frame picture in VOBU) can beextracted from an address designated by the start address ofrepresentation picture VOBU (RPV_SA) and the flame number inrepresentation picture VOBU (RIP_FN).

[0391] The data structure shown in FIG. 32 will be explained. As shownin the upper stage in FIG. 32, RTRW video manager information(RTRW_VMGI) 1021 includes a video manager information table (VMGI_MAT)and a play list pointer table (PL_LPT). As shown in the middle stage inFIG. 32, the video manager information management table (VMGI_MAT)includes a 12 byte (0 to 11) VMG identifier (VMG_ID), a 4 byte (12 to15) end address of RTRWI (RTRWI_EA), a 1 byte (16 to 16) program numberin representative picture (RPVOB_N), a 4 byte (27 to 20) time ofrepresentative picture in program (RP_ST), a 7 byte (21 to 27) reserved,a 4 byte (28 to 31) end address of VMGI (VMGI_EA), a 2 byte (32 to 33)version number of DVD RTRW video specification (VERN), and a 2,014 byte(34 to 2,047) reserved. A target representative picture can be extractedfrom a time designated by the program number in representative picture(RPVOB_N) and the time of representative picture in program (RP_ST).

[0392] A target representative picture can be extracted from theabove-described data. The extracted representative picture is directlyprinted on the disc or label, or displayed as a preview representing therecording contents of the disc. Printing is basically the same asdescribed above with reference to FIG. 21.

[0393] <5> Contents of Original PGC Information (ORG_PGCI)

[0394]1024 and User Defined PGC Information Table

[0395] (ORG_PGCI) 1025

[0396] The contents of original PGC information (ORG_PGCI) 1024 and userdefined PGC information table (ORG_PGCI) 1025 will be described withreference to FIGS. 33 and 34. PGC control information 1103 in originalPGC information (ORG_PGCI) 1024 and user defined PGC information table(ORG_PGCI) 1025 has a data structure shown in FIG. 33, and the playbackorder is determined by the PGC and cell. The PGC is a unit for executinga series of playback processes which designate the playback order ofcells. The cell is a playback section of playback data in each VOB thatis designated by start and end addresses, as shown in FIG. 27.

[0397] PGC control information 1103 consists of PGC informationmanagement information 1052, one or more search pointers of PGCinformation 1053 and 1054, and PGC information 1055, 1056, and 1057.

[0398] PGC information management information 1052 includes number ofPGC information indicating the number of PGCs. Each of search pointersof PGC information 1053 and 1054 points the beginning of each PGCinformation to facilitate search. Each of PGC information 1055, 1056,and 1057 consists of PGC general information 1061, and one or more cellplayback information 1062 and 1063. PGC general information 1061includes number of cell playback information serving as informationindicating the PGC playback time and the number of cells.

[0399] As shown in FIG. 34, playback data in the playback section fromcell-A to cell-F is designated in units of cells, and PGC information isdefined in each PGC.

[0400] (1) PGC#1 represents an example in which playback data consistsof cells designating a continuous playback section, and the playbackorder is cell-A→cell-B→cell-C.

[0401] (2) PGC#2 represents an example in which playback data consistsof cells designating a discontinuous playback section, and the playbackorder is cell-D→cell-E→cell-F.

[0402] (3) PGC#3 represents an example in which playback data can beskippingly played back regardless of the playback direction and multipleplayback, and the playback order is cell-E→cell-A→cell-D→cell-B→ cell-E.

[0403] The aforementioned embodiment and modification have exemplifiedthe RAM disc, but the present invention is not limited to this. Forexample, the present invention may be applied to the ROM disc. The aboveembodiment has exemplified the case in which the representative pictureis a base picture (I picture), but the present invention is not limitedto this. For example, the representative picture may be a picture basedon change data representing a change (motion) in base picture.

[0404] Further, the above-described embodiment and modification havedescribed the case in which the representative picture is printed basedon representative picture data, but the present invention is not limitedto this. For example, representative picture data may be stored in thememory (microcomputer block 30), and an icon may be generated from thestored representative picture data. The icon is generated bymicrocomputer block 30 and displayed on DVD video recorder display 48.In this manner, representative picture data can be used as a materialfor an icon.

1. An information reproducing method for reproducing a discrepresentative picture recorded on an information recording disc,wherein the information recording disc includes a first area for amanaging file in which management information is stored, and a secondarea for an audio file or a video file in which audio or videoinformation is stored, the information recording disc having at leastone object recorded in the audio or video file and managementinformation recorded in the managing file, said object includes objectunits, said object units each include at least one of a video pack inwhich video data is recorded and an audio pack in which audio data isrecorded, and said management information include a management table, aplurality of program chain information included in original programchain information, a plurality of cell information, and discrepresentative picture information for one disc representative picture,said plurality of program chain information designates respective cellreproduction orders, said plurality of cell information representsportions of the object, said disc representative picture informationincludes information regarding a program chain number included in theoriginal program chain information, a cell number, and a picture pointas a presentation time of a picture representing recording contents ofthe disc in the object unit, and information regarding a time when thedisc representative picture was made, said disc representative pictureis any of pictures included in the object, said management tableincludes a start address of said original program chain information, andsaid program chain information includes associated general informationand associated cell information in this order, the informationreproducing method comprising: a first step of reading said managementinformation, referring to the management table, the original programchain information, the plurality of cell information, and discrepresentative picture information, and determining a position of thedisc representative picture in the audio file or video file; a secondstep of reading the disc representative picture based on the positiondetermined by the first reading step; and a third step of decoding thedisc representative picture read by the second reading step.
 2. Aninformation reproducing method according to claim 1, wherein said discrepresentative picture is one of the pictures included in said objectthat is managed by said original program chain information.
 3. Aninformation reproducing apparatus for reproducing a disc representativepicture recorded on an information recording disc, wherein theinformation recording disc includes a first area for a managing file inwhich management information is stored, and a second area for an audiofile or a video file in which audio or video information is stored, theinformation recording disc having at least one object recorded in theaudio or video file and management information recorded in the managingfile, said object includes object units, said object units each includeat least one of a video pack in which video data is recorded and anaudio pack in which audio data is recorded, and said managementinformation includes a management table, a plurality of program chaininformation included in original program chain information, a pluralityof cell information, and disc representative picture information for onedisc representative picture, said plurality of program chain informationdesignates respective cell reproduction orders, said plurality of cellinformation represents portions of the object, said disc representativepicture information includes information regarding a program chainnumber included in the original program chain information, a cellnumber, and a picture point as a presentation time of a picturerepresenting recording contents of the disc in the object unit, andinformation regarding a time when the disc representative picture wasmade, said disc representative picture is any picture included in theobject, said management table includes a start address of said originalprogram chain information, and said original program chain informationincludes associated general information and associated cell informationin this order, the information reproducing apparatus comprising: firstmeans for reading said management information, referring to themanagement table, the original program chain information, the pluralityof cell information, and disc representative picture information, anddetermining a position of the disc representative picture in the audiofile or video file, second means for reading the disc representativepicture based on the position determined by the first means; and thirdmeans for decoding the disc representative picture read by the secondmeans.
 4. An information recording method for recording data on aninformation recording disc that includes a first area for a managingfile in which management information is stored, and a second area for anaudio file or a video file in which audio or video information isstored, the information recording method comprising: recording at leastone object in the audio or video file on the information recording disc,wherein said object includes object units and said object units eachinclude at least one of a video pack in which video data is recorded andan audio pack in which audio data is recorded; and recording managementinformation in the managing file, wherein said management informationincludes a management table, a plurality of program chain informationincluded in an original program chain information, a plurality of cellinformation, and disc representative picture information for one discrepresentative picture, said plurality of program chain informationdesignates respective cell reproduction orders, said cells representportions of the object, said disc representative picture informationincludes information regarding a program chain number included in theoriginal program chain information, a cell number, and a picture pointas a presentation time of a picture representing recording contents ofthe disc in the object unit, and information regarding a time when thedisc representative picture was made, said disc representative pictureis any picture included in the object, said management table includes astart address of said original program chain information, and saidprogram chain information includes associated general information andassociated cell information in this order.
 5. An information recordingapparatus according to claim 4, wherein said disc representative pictureis one of the pictures that is determined by a program chain included insaid original program chain information.
 6. An information recordingapparatus for recording data on an information recording disc thatincludes a first area for a managing file in which managementinformation is stored, and a second area for an audio file or a videofile in which audio or video information is stored, the informationrecording apparatus comprising: first means for recording at least oneobject in the audio or video file on the information recording disc,wherein said object includes object units and said object units eachinclude at least one of a video pack in which video data is recorded andan audio pack in which audio data is recorded; and second means forrecording management information in the managing file, wherein saidmanagement information includes a management table, a plurality ofprogram chain information included in an original program chaininformation, a plurality of cell information, and disc representativepicture information for one disc representative picture, said pluralityof program chain information designates respective cell reproductionorders, said cells represent portions of the object, said discrepresentative picture information includes information regarding aprogram chain number included in the original program chain information,a cell number, and a picture point as a presentation time of a picturerepresenting recording contents of the disc in the object unit, andinformation regarding a time when the disc representative picture wasmade, said disc representative picture is any picture included in theobject, said management table includes a start address of said originalprogram chain information, and said program chain information includesassociated general information and associated cell information in thisorder.
 7. An information recording/reproducing medium forrecording/reproducing a disc representative picture, comprising: a firstarea of a managing file in which management information is stored; and asecond area of an audio file or a video file in which audio or videoinformation is stored, a third area being provided in the second area,wherein the audio or video file includes at least one object, saidobject including object units, said object units each including at leastone of a video pack in which video data is recorded and an audio pack inwhich audio data is recorded, and a fourth area being provided in saidfirst area, wherein the managing file includes management information,said management information includes a management table, a plurality ofprogram chain information included in original program chaininformation, a plurality of cell information, and disc representativepicture information for one disc representative picture, said pluralityof program chain information designates respective cell reproductionorders, said cell information represents portions of the object, saiddisc representative picture information includes information regarding aprogram chain number belonging to the original program chaininformation, a cell number, and a picture point as a presentation timeof a picture representing recording contents of the disc in the objectunit, and information regarding a time when the disc representativepicture was made, said disc representative picture is any pictureincluded in the object, said management table includes a start addressof said original program chain information, and said original programchain information includes associated general information and associatedcell information in this order.